Limit the length of Darwin shared library version number.
diff --git a/configure b/configure
index 1a7e897..7aaf5df 100755
--- a/configure
+++ b/configure
@@ -44,7 +44,7 @@
 
 # extract zlib version numbers from zlib.h
 VER=`sed -n -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < ${SRCDIR}zlib.h`
-VERN=`echo ${VER}|sed -n -e 's/\([0-9]\{1,\}\(\\.[0-9]\{1,\}\)\{1,\}\).*/\1/p'`
+VER3=`echo ${VER}|sed -n -e 's/\([0-9]\{1,\}\(\\.[0-9]\{1,\}\)\{1,2\}\).*/\1/p'`
 VER1=`echo ${VER}|sed -n -e 's/\([0-9]\{1,\}\)\\..*/\1/p'`
 
 # establish commands for library building
@@ -264,7 +264,7 @@
         SHAREDLIB=libz$shared_ext
         SHAREDLIBV=libz.$VER$shared_ext
         SHAREDLIBM=libz.$VER1$shared_ext
-        LDSHARED=${LDSHARED-"$cc -dynamiclib -install_name $libdir/$SHAREDLIBM -compatibility_version $VER1 -current_version $VERN"}
+        LDSHARED=${LDSHARED-"$cc -dynamiclib -install_name $libdir/$SHAREDLIBM -compatibility_version $VER1 -current_version $VER3"}
         if "${CROSS_PREFIX}libtool" -V 2>&1 | grep Apple > /dev/null; then
             AR="${CROSS_PREFIX}libtool"
         elif libtool -V 2>&1 | grep Apple > /dev/null; then