Having the same problem. Can you tell me exactly which key you modified and from what to what? That would be amazingly helpful!

Edit: Never mind, here's the info:

\HKEY_LOCAL_MACHINE\Software\Opera\UA\

Change User Agent from:
Opera/9.5 (Microsoft Windows; Windows CE; Opera Mobi/9.5; U; en) VZW:SCH-i770 PPC 320x320

to:

Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; PPC; 320x320) Opera VZW:SCH-i770

Worked like a charm for me, no soft reset needed.