Recently I started a small project to build an incremental sql database of meta information related to debian packages. In the process I discovered that the newly available feature of sqlite3 to add custom collation doesn't work well with the sqlite3 bindings present in python 2.5 . The reason is that in order to load a collation at run time, you must explicitly enable the extension loading mechanism. The binding present in python 2.5 (fixed in python 2.6) do not expose this C function.