Reading on the Infogrames forums, one of the UT programmers responded to somebody suggesting to up the cache size of UT with "NO!!! It's 32 megs for a reason! LEAVE IT ALONE!", so I went back to 32. Can't really tell a difference, but oh well.
And yes, I DO mean the Windows pagefile. 512 megs is all you need... have been running that way all night with no problems.