I remember reading somewhere that substantial changes were made to web/java related stuff in 4.2.1, and that included font types. I'm suspecting that's your issue. Now exactly where I read that, I couldn't tell you at this point...
While it won't get you the font that the widget was designed with, you can always change fonts in the HTML by specifying a new one under the style section for each item element. Most of the time, changing those to Helvetica will get you whatever system font you have specified. I'll sometimes use Bytafont to specify a different font for the Dialer, and then change the font listed in the HTML to "PhonepadTwo"--that way I can use a font that doesn't work well for reading mail, but looks great on a lockscreen, for example.