I knew the "fontincrement" works in Windows XP, but I'm talking about Windows 7x64bit. Did your team ever do any test in windows 7x64? The "fondincrement" doesn't work at all, at least in my laptop (Lenovo W520, windows 7x64, JRE 1.4.2.19). However, if I switch to JRE 1.5.14 or higher, it works.
Also, there's nothing to do with the screen resolution. I just tested with a 1024x768 LCD from junk room, it displays exactly the same thing. Refer to the attached picture, I just collect some words to show how difficult to read.
Refer to the attached picture, the settings are:
"fontincrement 3", windows 7x64, JRE 1.4.2.19, 1024x768 LCD screen.
Please, ask your team to find a Windows 7x64, test it out, and let me know what to do.
BTW, Windows XP was not available since 2010 Oct, and will be end of support in 2014. It would be better for yor team to develop something in Windows 7.