I have a Citrix farm running Xenapp 5.0 on W2k3, which is essentially XenApp 4.5. This is the highest version of Xenapp that works on W2k3 servers. I am introducing a new W2k8 application server, which can run the latest greatest version of Xenapp but it's my understanding that Xenapp 6.0 and higher cannot coexist in the same farm as Xenapp 5.0. Can I run Xenapp 5.0, FP 3 on my W2k8 box? Or should I stay at plain Xenapp 5.0 without the feature pack? Are there any other farm level compatibility issues i should be worried about? Thanks in advance.