Typically one would use the following line in .pro file to define a string to pass as -D parameters for compiler:

DEFINES += VERSION_STR=\\\"1.2.3\\\"

This will break in symbian-sbsv2, where '\' characters will be interpreted to be part of the string. This would work in symbian-sbsv2:

DEFINES += VERSION_STR=\"1.2.3\"

It would be nice if developer didn't have to define these string defines separately from symbian and other platforms, so qmake should detect these cases and strip the extra backslashes away.

Unfortunately, for symbian-abld, nothing can be done, except maybe print a warning; the toolchain simply doesn't support string defines in .mmp files.