diff --git a/pkgtool.pm b/pkgtool.pm
index 8501ce3..39b9f99 100644
--- a/pkgtool.pm
+++ b/pkgtool.pm
@@ -646,6 +646,16 @@ sub read_os_patches ($$)
 		next unless $original || $update;
 		my $kb = $1;
 		my $number = $kb =~ /^(\d+)/o ? $1 : $kb;
+		if ($installname =~ /^[^~]*KB\d[0-9a-zA-Z]+~[^~]*~[^~]*~[^~]*~(\d+(\.\d+)*)/o) {
+			my $version = $1;
+			if (defined $version && $version ne '') {
+				my @versionlist = split /\./, $version;
+				my $revnum = $versionlist[2];
+				if (defined $revnum && $revnum =~ /^\d+$/o && $revnum > 1) {
+					$kb .= 'v'.$revnum;
+				}
+			}
+		}
 		my $p = $$patches{$kb};
 		if (! defined $p) {
 			$p = $$patches{$kb} = {