iPhone iTunes delimma

I have an older iMac (2006) with OSX 10.4 Tiger. I just purchased a new iPhone 4. I found out I have to have the latest version of iTunes to be able to sync my music to my iPhone, from th iMac. Well, Tiger won't take the latest version of iTunes. I have a PC that is linked on a wireless network to the iMac. The PC has the latest itunes upgrade. I can get the iTunes from the iMac to show up and play from the PC. Is there any way to either sync the iPhone from the Home Share on the PC, OR load the songs from the iMac via Home Share to the PC? If not, I know I can upgrade the iMac to Leopard, and that should do it, but I would rather just sync the iPhone from the PC...if possible.
Thanks for any help,
Steve

If you're refusing to upgrade your old Mac, then the best thing I can suggest is that you transfer your existing (Mac) iTunes Library en masse over to the PC and use the PC as your "home base" for the iPhone.

As a general rule of thumb for future info: the latest electronics (from any company) tend to want to work with the latest computers and software (not the VERY latest, but within the last few years). This is based on an expected average lifecycle of a personal computer to range from 2-4 years.

I would personally think upgrading to Leopard (10.5.8) would be faster and easier in the short term, but obtaining a retail copy of Leopard is going to prove tricky.