Добавил в configure.ac проверку на существование mysql.h

Utilities/DBServer-MySQL/Makefile.am

-############################################################################
-# This file is part of the UniSet library                                  #
-############################################################################
-
 UMYSQL_VER=@LIBVER@
 
 lib_LTLIBRARIES 			= libUniSet-mysql.la
 libUniSet_mysql_la_LDFLAGS  = -version-info $(UMYSQL_VER) 
 libUniSet_mysql_la_SOURCES	= DBInterface.cc DBServer_MySQL.cc
 libUniSet_mysql_la_LIBADD	= $(top_builddir)/lib/libUniSet.la -lmysqlclient
-libUniSet_mysql_la_LDFLAGS	= -version-info @LIBVER@
 
 bin_PROGRAMS 					= uniset-mysql-dbserver
 uniset_mysql_dbserver_LDADD		= libUniSet-mysql.la $(top_builddir)/lib/libUniSet.la
@@ -19,4 +14,3 @@ include $(top_builddir)/conf/setting.mk
 # install
 devel_include_HEADERS = *.h
 devel_includedir = $(includedir)/@PACKAGE@/mysql
-

configure.ac

@@ -53,17 +53,18 @@ test "x$IDL" = "x" && AC_MSG_ERROR([*** omniidl not found.])
 
 #check mysql support
 AC_MSG_CHECKING([mysql support])
-dmysql=false
+buildmysql=true
 AC_ARG_ENABLE(mysql, AC_HELP_STRING([--disable-mysql], [disable MySQL support]),
-[ if test $enableval = yes; then dmysql=false; else dmysql=true; fi],[ dmysql=false; ])
+[ if test $enableval = yes; then buildmysql=true; else buildmysql=false; fi],[ buildmysql=true; ])
 
-if test ${dmysql} = false; then
-	AC_MSG_RESULT([yes])
+if test ${buildmysql} = true; then
+	AC_MSG_RESULT([enabled])
+	AC_CHECK_HEADERS([mysql/mysql.h])
 else
-	AC_MSG_RESULT([no])
+	AC_MSG_RESULT([disabled])
 fi
 
-AM_CONDITIONAL(DISABLE_MYSQL, test ${dmysql} = true)
+AM_CONDITIONAL(DISABLE_MYSQL, test ${buildmysql} = false)
 
 #check build extensions
 ext=true