Question about firefox

[jerry]

I am running Kubuntu 8.04 and using firefox 3.0.14 and have a sometimes 
intermittent problem with firefox. I have over 1 GB ram and a P4 cpu.
It usually happens intermittently and repairs itself, but the only way 
that I can reproduce the problem consistently is to go to the website 
http://www.picnik.com/
and try to upload a photo. The site says that it is compatible with 
linux. When I upload a photo (actually a jpg that I use for a wallpaper) 
it uploads the jpg and very soon firefox turn black and white and shades 
of gray and locks up. I have to kill firefox, but all other programs are 
not affected. I have tried to do it in firefox safe-mode (all addons 
disabled) and the problem still occurs. I have pasted the end of dmesg 
at the bottom of the post but it does not appear relevant to me.
Appreciate any ideas about what is going on and how to correct it.
Thanks

Jerry
end of dmesg
 53.492828] agpgart: Found an AGP 3.0 compliant device at 0000:00:00.0.
[   53.492846] agpgart: Putting AGP V3 device at 0000:00:00.0 into 8x mode
[   53.492881] agpgart: Putting AGP V3 device at 0000:01:00.0 into 8x mode
[   55.468046] e1000: eth0: e1000_watchdog: NIC Link is Up 100 Mbps Full 
Duplex, Flow Control: RX/TX
[   55.469724] ADDRCONF(NETDEV_UP): eth0: link is not ready
[   55.473775] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[   59.855338] NET: Registered protocol family 17
[   73.132309] eth0: no IPv6 routers present