Friedrich, Oliver wrote:
Alright, just found out, where this variable was set. It is set on the commandline while calling the batch-file to start the compilation of the setup.
The batch-file is called as "Pre-build event command line" in VS2005. The variable "var.Build" is set to the value of "$(ConfigurationName)". The last is homemade of VisualStudio. How can I access this "ConfigurationName" under WiX-V3?

WiX doesn't support that as it's a Visual Studio-specific concept. Votive might, though. JRock?