Allow build to proceed even if libhpi.so is not present

(cherry picked from commit efdff81cd2)

acinclude.m4.in

@@ -5726,12 +5726,6 @@ if test "x$kde_java_bindir" != "xno"; then
 
   dnl not needed for gcj compile
 
-  if test "x$kde_java_libgcjdir" = "x"; then 
-      if test ! -r "$kde_java_libhpidir/libhpi.so"; then
-        AC_MSG_ERROR([libhpi.so not found under $kde_java_libhpidir. Use --without-java.])
-      fi
-  fi
-
   if test -n "$jni_includes"; then
     dnl Check for JNI version
     AC_LANG_SAVE
@@ -5768,8 +5762,12 @@ if test "x$kde_java_bindir" != "xno"; then
     JAVAH=$kde_java_bindir/javah
     JAR=$kde_java_bindir/jar
     AC_DEFINE_UNQUOTED(PATH_JAVA, "$kde_java_bindir/java", [Define where your java executable is])
-    if test "x$kde_java_libgcjdir" = "x"; then 
-      JVMLIBS="-L$kde_java_libjvmdir -ljvm -L$kde_java_libhpidir -lhpi"
+    if test "x$kde_java_libgcjdir" = "x"; then
+      if test ! -r "$kde_java_libhpidir/libhpi.so"; then
+        JVMLIBS="-L$kde_java_libjvmdir -ljvm"
+      else
+        JVMLIBS="-L$kde_java_libjvmdir -ljvm -L$kde_java_libhpidir -lhpi"
+      fi
     else
       JVMLIBS="-L$kde_java_libgcjdir -lgcj"
     fi