Can anyone tell me why my wire frames look like the first picture when they should look like the second;

Clicking around randomly sometimes changes it back and forth.
I’m using Blender 2.48 in Ubuntu Hardy Heron but haven’t used it for months so I’m guessing one of the ATI updates borked, but they seem to check out;
fglrxinfo
display: :0.0 screen: 0
OpenGL vendor string: ATI Technologies Inc.
OpenGL renderer string: RADEON X800 PRO
OpenGL version string: 2.1.7412 Release
uname -r
2.6.24-22-generic
glxinfo
name of display: :0.0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.2
server glx extensions:
etc
glxgears
46607 frames in 5.0 seconds = 9321.202 FPS
46629 frames in 5.0 seconds = 9325.666 FPS
46606 frames in 5.0 seconds = 9321.101 FPS
46634 frames in 5.0 seconds = 9326.766 FPS
44101 frames in 5.0 seconds = 8820.149 FPS
46086 frames in 5.0 seconds = 9217.093 FPS
blender
Compiled with Python version 2.5.2.
Checking for installed Python... got it!