I've had the problem with my iChat Jabber connections (gtalk and yahoo.jabber.org.uk gateway) constantly crashing, causing an error dialog in iChat. Since the Chax add-on no longer seems to support automatically reconnecting to crashed connections in 10.5, I found this great idea for a crontab script to force a reconnection using AppleScript. However, the only problem is that this would start iChat even if it was not running.
So I used this slightly extended script to make it check if iChat was running before executing the login command. I added this line to my crontab (via crontab -e or the Cronnix crontab editor) to make it re-run every minute using the command line:
Mac OS X Hints
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