Allow defining "-mmacosx-version-min=10.5" in macports.conf

[ruibmartins@…]

Basically I upgraded to Snow Leopard and now I can no longer produce bundles of my application that contain dylibs from MacPorts because all dylib only work in 10.6.

The only work around would be for me to downgrade the system to Leopard but that's a bit to ask. I'll have to compile all delegate libraries manually instead.

I think a few developers will bump into this issue and will either move to Fink since it only supports 10.5 or will just have to compile it manually like me.

Thanks, Rui

[jmr@…]

#19875