A viable alternative to Oxygen Manager, that I guarantee works flawlessly in Win 98SE is
MobTime Cell Phone Manager 2006 (at least up to v. 6.0.9, which is the one I now use).
It is shareware, like Oxygen Manager. And it is very resource-hungry, meaning you must
run it almost alone or else your system resources will drop to 0%! But, then again, you
don't need to access your mobile phone longer than to be able to back-up your data or
to upload things to the phone or to download from it, hence its resouce-hunger is not a
very big nuisance, IMHO, but YMMV, of course. My phone, BTW, is a Nokia 6111.
The link to find it is:
http://www.mobtime.com HTH