Just the other day, I encountered a mysterious error which may or may not be related. I upgraded to pdftex 1.40.7 on all my boxes. This was smooth on my intel-macs (OS X 10.5.2). On my powerpc-mac, I got a "TeX capacity exceeded!" error with 1.40.7 for a file that compiled fine with 1.40.5. I tried several times: all I did was dropping the pdftex binary and pdftex.pool in place, rebuilding th format and compiling the file. Compilation was smooth with 1.40.5 and consistently failed with 1.40.7 (which I compiled and recompiled without any special flags). I haven't pursued the matter for the moment and just went back to 1.40.5, but I'm wondering if these problems are related. Do you have a test file ?
-- luigi it's new . it's powerful . it's luatex . http://www.luatex.org