diff --git a/HISTORY b/HISTORY
index 1c1199c3..082e58ea 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,5 +1,8 @@
 amath release history
 
+v1.8.1 May 1 2017
+- OpenBSD support
+
 v1.8.0 April 13 2017
 - Fixed bugs in numeral systems.
 - Fixed bugs related to infinity (Inf).
diff --git a/amath.1 b/amath.1
index 3707d586..29a51737 100644
--- a/amath.1
+++ b/amath.1
@@ -20,7 +20,7 @@
 .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-.TH amath 1 "Version 1.8.0" "April 13 2017"
+.TH amath 1 "Version 1.8.1" "May 1 2017"
 .SH NAME
 amath \- Simple command line calculator
 .SH SYNOPSIS
diff --git a/amath.doxygen b/amath.doxygen
index 8404be48..403f73c6 100644
--- a/amath.doxygen
+++ b/amath.doxygen
@@ -1,7 +1,7 @@
 
 DOXYFILE_ENCODING      = UTF-8
 PROJECT_NAME           = "amath"
-PROJECT_NUMBER         = "1.8.0"
+PROJECT_NUMBER         = "1.8.1"
 PROJECT_BRIEF          = "Simple command line calculator"
 PROJECT_LOGO           =
 OUTPUT_DIRECTORY       = ../amath-doc
diff --git a/builddebdev b/builddebdev
index 882f491b..fce88b65 100755
--- a/builddebdev
+++ b/builddebdev
@@ -2,7 +2,7 @@
 
 set -e
 
-version="1.8.0"
+version="1.8.1"
 
 build_package () {
 
diff --git a/buildsrc b/buildsrc
index 61cd1a01..4a53be83 100755
--- a/buildsrc
+++ b/buildsrc
@@ -2,7 +2,7 @@
 
 # DO NOT USE THIS SCRIPT UNLESS YOU KNOW WHAT YOU ARE DOING !
 
-version='1.8.0'
+version='1.8.1'
 stamp="201704130000"
 #stamp="201704110000"
 srcdir="amath-rc"
diff --git a/buildwin b/buildwin
index 930a567f..e6465624 100755
--- a/buildwin
+++ b/buildwin
@@ -2,7 +2,7 @@
 
 set -e
 
-version="1.8.0"
+version="1.8.1"
 
 echo "Building amath ${version} for Windows ..."
 
diff --git a/configure b/configure
index e6630392..2814e14c 100755
--- a/configure
+++ b/configure
@@ -27,7 +27,7 @@
 
 set -e
 
-version="1.8.0"
+version="1.8.1"
 
 clang=false
 debugsym=false
diff --git a/src/amath.h b/src/amath.h
index 3e05bbfc..06a5eed1 100644
--- a/src/amath.h
+++ b/src/amath.h
@@ -281,9 +281,9 @@ typedef int bool;
 #endif
 /******************************************************************************/
 #define TXTARCH          TXTCPU TXTFPU
-#define RELDATESTAMP     "(13-04-2017)"
-#define TXTDOSVERSION    "\0$VER: amath 1.80" SPACE RELDATESTAMP SPACE TXTARCH
-#define TXTTITLE         "amath version 1.8.0"
+#define RELDATESTAMP     "(01-05-2017)"
+#define TXTDOSVERSION    "\0$VER: amath 1.81" SPACE RELDATESTAMP SPACE TXTARCH
+#define TXTTITLE         "amath version 1.8.1"
 #define TXTCOPYRIGHT     "(c) 2017 Carsten Sonne Larsen"
 #define TXTSTARTMSG      TXTTITLE SPACE TXTCOPYRIGHT
 /******************************************************************************/
diff --git a/src/clib/amathc.3 b/src/clib/amathc.3
index 0a4a124c..f1573b81 100644
--- a/src/clib/amathc.3
+++ b/src/clib/amathc.3
@@ -20,7 +20,7 @@
 .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-.TH "amathc.h" 3 "Version 1.8.0" "April 13 2017"
+.TH "amathc.h" 3 "Version 1.8.1" "May 1 2017"
 .SH NAME
 amathc.h \- C functions for manipulating strings and memory
 .SH SYNOPSIS
diff --git a/src/clib/amathc.dox b/src/clib/amathc.dox
index 77702724..26282f34 100644
--- a/src/clib/amathc.dox
+++ b/src/clib/amathc.dox
@@ -1,7 +1,7 @@
 
 DOXYFILE_ENCODING      = UTF-8
 PROJECT_NAME           = "amathc"
-PROJECT_NUMBER         = "1.8.0"
+PROJECT_NUMBER         = "1.8.1"
 PROJECT_BRIEF          = "C functions for manipulating strings and memory"
 PROJECT_LOGO           =
 OUTPUT_DIRECTORY       = 
diff --git a/src/clib/amathc.pc b/src/clib/amathc.pc
index f1e8c8cd..2de11192 100644
--- a/src/clib/amathc.pc
+++ b/src/clib/amathc.pc
@@ -5,6 +5,6 @@ libdir=${exec_prefix}/lib
 
 Name: amath C library
 Description: C functions for manipulating strings and memory
-Version: 1.8.0
+Version: 1.8.1
 Cflags: -I${includedir}
 Libs: -L${libdir} -lamathc
diff --git a/src/cplex/amathi.3 b/src/cplex/amathi.3
index 61dea149..8607f678 100644
--- a/src/cplex/amathi.3
+++ b/src/cplex/amathi.3
@@ -20,7 +20,7 @@
 .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-.TH "mathi.h" 3 "Version 1.8.0" "April 13 2017"
+.TH "mathi.h" 3 "Version 1.8.1" "May 1 2017"
 .SH NAME
 mathi.h \- Complex numbers math library
 .SH SYNOPSIS
diff --git a/src/cplex/amathi.dox b/src/cplex/amathi.dox
index 612a1ed7..90ae6f6a 100644
--- a/src/cplex/amathi.dox
+++ b/src/cplex/amathi.dox
@@ -1,7 +1,7 @@
 
 DOXYFILE_ENCODING      = UTF-8
 PROJECT_NAME           = "amathi"
-PROJECT_NUMBER         = "1.8.0"
+PROJECT_NUMBER         = "1.8.1"
 PROJECT_BRIEF          = "Complex numbers math library"
 PROJECT_LOGO           =
 OUTPUT_DIRECTORY       = 
diff --git a/src/cplex/amathi.pc b/src/cplex/amathi.pc
index b21b1e77..e9178915 100644
--- a/src/cplex/amathi.pc
+++ b/src/cplex/amathi.pc
@@ -5,6 +5,6 @@ libdir=${exec_prefix}/lib
 
 Name: amath complex library
 Description: Complex numbers math library
-Version: 1.8.0
+Version: 1.8.1
 Cflags: -I${includedir}
 Libs: -L${libdir} -lamathi
diff --git a/src/lib/amatha.pc b/src/lib/amatha.pc
index 3d0dd104..7c8ed846 100644
--- a/src/lib/amatha.pc
+++ b/src/lib/amatha.pc
@@ -5,6 +5,6 @@ libdir=${exec_prefix}/lib
 
 Name: amath application library
 Description: C++ library for handling numbers
-Version: 1.8.0
+Version: 1.8.1
 Cflags: -I${includedir}
 Libs: -L${libdir} -lamathapp -lamathr -lamathi -lamathc
diff --git a/src/main.h b/src/main.h
index 103cb068..c413f410 100644
--- a/src/main.h
+++ b/src/main.h
@@ -261,6 +261,9 @@
   \page    release_page Release history
   \section release_sec  Release history
 
+  \subsection version181 1.8.1 May 1 2017
+  - OpenBSD support
+
   \subsection version180 1.8.0 April 13 2017
   - Fixed bugs in numeral systems.
   - Fixed bugs related to infinity (Inf).
diff --git a/src/real/amathr.3 b/src/real/amathr.3
index 40279e48..83831afc 100644
--- a/src/real/amathr.3
+++ b/src/real/amathr.3
@@ -20,7 +20,7 @@
 .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-.TH "mathr.h" 3 "Version 1.8.0" "April 13 2017"
+.TH "mathr.h" 3 "Version 1.8.1" "May 1 2017"
 .SH NAME
 mathr.h \- Real numbers math library 
 .SH SYNOPSIS
diff --git a/src/real/amathr.dox b/src/real/amathr.dox
index 0a419647..c45847bf 100644
--- a/src/real/amathr.dox
+++ b/src/real/amathr.dox
@@ -1,7 +1,7 @@
 
 DOXYFILE_ENCODING      = UTF-8
 PROJECT_NAME           = "amathr"
-PROJECT_NUMBER         = "1.8.0"
+PROJECT_NUMBER         = "1.8.1"
 PROJECT_BRIEF          = "Real numbers math library"
 PROJECT_LOGO           =
 OUTPUT_DIRECTORY       = 
diff --git a/src/real/amathr.pc b/src/real/amathr.pc
index cce0f267..7a705c1e 100644
--- a/src/real/amathr.pc
+++ b/src/real/amathr.pc
@@ -5,6 +5,6 @@ libdir=${exec_prefix}/lib
 
 Name: amath real library
 Description: Real numbers math library
-Version: 1.8.0
+Version: 1.8.1
 Cflags: -I${includedir}
 Libs: -L${libdir} -lamathr