I recently came upon a weird and obscure problem with Ubuntu 9.04 and intel 4965AGN wireless adapters. Apparently in an area with a high density of access points one cannot connect. This was / is a known issue ( http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=1885 ). I believe this maybe a regression. I switched to Fedora 11 and kernel 2.6.29 and upwards dont exhibit the same issue.
Just a heads up for everyone! -- Regards, Dinesh A. Joshi -- http://mm.glug-bom.org/mailman/listinfo/linuxers
