=== modified file 'mixxx/src/library/basesqltablemodel.cpp'
--- mixxx/src/library/basesqltablemodel.cpp	2010-05-20 07:23:14 +0000
+++ mixxx/src/library/basesqltablemodel.cpp	2010-05-28 21:31:10 +0000
@@ -134,7 +134,9 @@
     // If the field is a string, sort using its lowercase form so sort is
     // case-insensitive.
     QVariant::Type type = f.type();
-    if (type == QVariant::String) {
+    if (sort_field.contains("tracknumber")) {
+        sort_field = QString("cast(%1 as integer)").arg(sort_field);
+    } else if (type == QVariant::String) {
         sort_field = QString("lower(%1)").arg(sort_field);
     }
     s.append(sort_field);