I am accustomed to Idea 3.5 and new to 4.5. In the 3.5 days, there were separate paths for project files and "sources" files. Now they seem to be merged and employ the "Source" and "Exclude" options. I find this very confusing.
I have some jar files that I also have sources for, but don't want these sources in the project, per se. But I can't access these sources via ctrl-B unless I make them "Sources".
When I "attached" the sources to the jar files, it didn't help matters. [Nite that these source files are not in the proper directory hierarchies per their packages, but that doesn't seem to matter if I make them "Sources"]