Check for jakarta-ant before ant, in case 'ant' is the screen saver program.

Then, run a small reality test with $ANT to see whether it works.

config/java.m4

 #
 # Autoconf macros for configuring the build of Java JDBC Tools
 #
-# $Header: /cvsroot/pgsql/config/Attic/java.m4,v 1.2 2001/03/11 11:24:59 petere Exp $
+# $Header: /cvsroot/pgsql/config/Attic/java.m4,v 1.3 2001/07/04 21:22:55 petere Exp $
 #
 
+
+# _PGAC_PROG_ANT_WORKS
+# --------------------
+AC_DEFUN([_PGAC_PROG_ANT_WORKS],
+[
+  AC_CACHE_CHECK([whether $ANT works], [pgac_cv_prog_ant_works],
+  [
+    cat > conftest.java << EOF
+public class conftest {
+    int testmethod(int a, int b) {
+        return a + b;
+    }
+}
+EOF
+
+    cat > conftest.xml << EOF
+<project name="conftest" default="conftest">
+ <target name="conftest">
+  <javac srcdir="." includes="conftest.java">
+  </javac>
+ </target>
+</project>
+EOF
+
+    pgac_cmd='$ANT -buildfile conftest.xml 1>&2'
+    AC_TRY_EVAL(pgac_cmd)
+    pgac_save_status=$?
+    if test $? = 0 && test -f ./conftest.class ; then
+      pgac_cv_prog_ant_works=yes
+    else
+      echo "configure: failed java program was:" >&AC_FD_CC
+      cat conftest.java >&AC_FD_CC
+      echo "configure: failed build file was:" >&AC_FD_CC
+      cat conftest.xml >&AC_FD_CC
+      pgac_cv_prog_ant_works=no
+    fi
+
+    rm -f conftest* core core.* *.core
+  ])
+
+  if test "$pgac_cv_prog_ant_works" != yes; then
+    AC_MSG_ERROR([ant does not work])
+  fi
+])
+
+
 # PGAC_PATH_ANT
 # -------------
 # Look for the ANT tool and set the output variable 'ANT' to 'ant'
 # if found, empty otherwise
 AC_DEFUN([PGAC_PATH_ANT],
-         [AC_PATH_PROGS(ANT, [ant ant.sh ant.bat])])
+[
+  AC_PATH_PROGS(ANT, [jakarta-ant ant ant.sh ant.bat])
+  _PGAC_PROG_ANT_WORKS
+])