Yeh, I wanted this too.. I see no reason to have different selection keys for each weapon type in MP when you can only ever have one weapon at any time.
To remedy this I created an alias that effectively should have selected each weapon type in turn (similar to yours), theoretically leaving the one up that you selected to start with.
I tried it on the demo. It works sporadically but it's really buggy. No reason for it to not work but there you go. I'll try it on the full game and see if I can work it out tonight.
I'll post here if I sort it.
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[This message has been edited by Ydiss (edited February 10, 2002).]