using v 1.3.51 build 280808A
Windows XP Pro SP 2

if you take multiple screenshots of someone with the same name, case insensitive, you get files like the following:

gaki (tc) is looking good!.tga
Gaki (TC) is looking good!_0000.tga
Gaki (TC) is looking good!_0001.tga

the screenshot browser displays the first two of these images as the same, although if i open the files in quicktime (oddly enough it seems like the default viewer for targa files on my machine), they're definitely different.

the pattern isn't completely consistent, for example, with the above example and these files:

the communist is looking good!.tga
The Communist is looking good!_0000.tga
The Communist is looking good!_0001.tga

the first two files are shown with the same image, but with these files:

the deerhaunter (tc) is looking good!.tga
The Deerhaunter (TC) is looking good!_0000.tga
The Deerhaunter (TC) is looking good!_0001.tga

the first and third are shown the same.

this behavior is consistent on restarting the application.