I have the problem on my Iyonix (www.iyonic.com) when using Aemulor 
(www.aemulor.com) because the DAs (google Dynamic Areas RISC OS Acorn) 
are placed in a high address range and  can start at just below 2Gb and 
obviously wrap over 2Gb. The only problem I've seen it cause so far is 
the failure of prim 99(?) that fiddles the oops in a loaded imagesegment.

As previously suggested I suspect that the problem may be solved as a 
side effect of the VM changes Ian has provided to support 64bit 
machines. If not, then it will likely be some more work of a similar 
nature to solve. The root cause is that assumption (remember, "assume 
makes an ASS out of U and ME") that singed int is a good type for oops. 
Actually, I suppose that the real root is the idea of types....

tim