diff --git a/korundum/rubylib/korundum/configure.in.in b/korundum/rubylib/korundum/configure.in.in
index 18299977..e1a84710 100644
--- a/korundum/rubylib/korundum/configure.in.in
+++ b/korundum/rubylib/korundum/configure.in.in
@@ -13,9 +13,12 @@ else
     RUBY_VERSION=`$PKGCONFIG ruby --modversion 2>/dev/null`
     if test -n "$RUBY_VERSION"; then
       RUBY_CFLAGS=`$PKGCONFIG ruby --cflags`
-    else
+    fi
+    if test -z "$RUBY_VERSION"; then
       RUBY_VERSION=`$PKGCONFIG ruby-1.9 --modversion 2>/dev/null`
-      RUBY_CFLAGS=`$PKGCONFIG ruby-1.9 --cflags`
+      if test -n "$RUBY_VERSION"; then
+        RUBY_CFLAGS=`$PKGCONFIG ruby-1.9 --cflags`
+      fi
     fi
     if test -z "$RUBY_VERSION"; then
       # pkgconfig file does not exist but might be 1.9.1: RUBY_VERSION defined in ruby/version.h
@@ -26,6 +29,8 @@ else
         RUBY_TEENY=`$RUBY -r rbconfig -e 'printf("%s",RbConfig::CONFIG@<:@"['TEENY']"@:>@)'`
         if test "$RUBY_MAJOR" == "1" && test "$RUBY_MINOR" == "9"; then
           RUBY_VERSION="$RUBY_MAJOR.$RUBY_MINOR.$RUBY_TEENY"
+          RUBY_CFLAGS="-I`$RUBY -r rbconfig -e 'printf("%s",RbConfig::CONFIG@<:@"rubyhdrdir"@:>@)'`"
+          RUBY_CFLAGS="$RUBY_CFLAGS/`$RUBY -r rbconfig -e 'printf("%s",RbConfig::CONFIG@<:@"arch"@:>@)'` $RUBY_CFLAGS"
         fi
       fi
     fi
@@ -60,9 +65,11 @@ else
                   cflags $RUBY_CFLAGS])
   AC_SUBST(RUBY_ARCHDIR)
   AC_SUBST(RUBY_SITEARCHDIR)
+  AC_SUBST(RUBY_SITEDIR)
   AC_SUBST(RUBY_RUBYLIBDIR)
+  AC_SUBST(RUBY_LIBDIR)
   AC_SUBST(RUBY_INCLUDEDIR)
-  AC_SUBST(RUBY_SITEDIR)
+  AC_SUBST(RUBY_LIBRUBYARG)
   AC_SUBST(RUBY_CFLAGS)
 fi
 
diff --git a/qtruby/rubylib/qtruby/configure.in.in b/qtruby/rubylib/qtruby/configure.in.in
index f8804038..f42716c4 100644
--- a/qtruby/rubylib/qtruby/configure.in.in
+++ b/qtruby/rubylib/qtruby/configure.in.in
@@ -8,6 +8,7 @@ if test -z "$RUBY"; then
   DO_NOT_COMPILE="$DO_NOT_COMPILE qtruby"
 else
   AC_MSG_CHECKING(for ruby dirs)
+  # Note: pkgconfig file exists only for ruby >= 1.9.3
   if test -n "$PKGCONFIG"; then
     RUBY_VERSION=`$PKGCONFIG ruby --modversion 2>/dev/null`
     if test -n "$RUBY_VERSION"; then