I have just posted an update to version 2.8.1 of OpenProofPower that makes it
compatible with compilation systems that default to 64-bit architecture, e.g.
Apple's Xcode tools as supplied with Mac OS X 10.6 (Snow Leopard).
If xpp complains on start-up about invalid mnemonics for cascade buttons, then
you very likely need this fix. If you don't know whether the compilation
system on your computer is 64-bit or not, then I recommend you use the fixed
code anyway, since it is simply more portable than previously. This fix also
cures some obscure but fairly harmless bugs with the options tool in xpp.
I have provide a patch to implement the fix which may be of interest if you
have a very very slow Internet connection, but have uploaded a patched source
release to make life simpler for others (this is now what you get by default
from the link on the "getting" page of the website).
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