diff --git a/src/resourcefiles/resourcefile.cpp b/src/resourcefiles/resourcefile.cpp
index d3949f5ed..b4d987810 100644
--- a/src/resourcefiles/resourcefile.cpp
+++ b/src/resourcefiles/resourcefile.cpp
@@ -407,8 +407,11 @@ void FResourceFile::PostProcessArchive(void *lumps, size_t lumpsize)
 	long len;
 	int lastpos = -1;
 	FString file;
-
-	while ((len = LumpFilterIWAD.IndexOf('.', lastpos+1)) > 0)
+	if (LumpFilter.IndexOf('.') < 0)
+	{
+		max -= FilterLumps(LumpFilter, lumps, lumpsize, max);
+	}
+	else while ((len = LumpFilterIWAD.IndexOf('.', lastpos+1)) > 0)
 	{
 		max -= FilterLumps(LumpFilterIWAD.Left(len), lumps, lumpsize, max);
 		lastpos = len;