In my PRS+ settings i couldnot check the use of css.Though i followed this link:
http://code.google.com/p/prs-plus/wiki/HowToCustomFonts
Downloaded their css,made directories,put it in.It readed-FontsAsInLRF.css:font-face
{
font-family: sans-serif;
src:url(res:///opt/sony/ebook/FONT/tt0003m_.ttf);
}
@font-face
{
font-family: serif;
src:url(res:///opt/sony/ebook/FONT/tt0011m_.ttf);
}
@font-face
{
font-family: monospace;
src:url(res:///opt/sony/ebook/FONT/tt0419m_.ttf);
}