I get the "cannot activate EDGE" message occasionally, but more often it's as if I can't resolve names. I'll have 3-4 bars and the E icon, but Safari tells me it can't access sites. When this happens, it happens for all sites, and I think an EDGE problem is more likely than google, my university, and apple.com all going down simultaneously. Toggling Airplane mode doesn't fix it. Short of rebooting the phone, is there a way to reset the IP stack?