I ran into a bug using allegro 4.0. On my duel core the code

set_display_switch_mode(SWITCH_BACKGROUND); //allows game to run in back ground

This dose not work. Is this fixed in the newer version of allegro.
I am thinking that it is a timing issue battelNet has patched there client for a similar problem.

Thanks for any help.

Read the docs more carefully. Its not supported on windows fullscreen. Use SWITCH_BACKAMNESIA.

This is somthing that use to work on the same O/S. i have just changed CUPs. i am in windowed mode, not fullscreen.

Try it and get back to us. Thanks.

There's plenty of those. Don't bother reporting about bugs in older versions of Allegro; as Peters said, upgrade and see if that fixes it.