I have never used virtualbox but I do use VMware Server in Foresight.
When I installed VMware Server, which also needs to be compiled, I got a message saying that my host OS (Foresight) was compiled using GCC 4.1.1 and that only GCC 4.1.2 was available to compile VMware Server. A stern warning was issued that this is not a good idea and it was recommended that I use the same compiler for Vmware Server as was used for the host OS (i.e GCC 4.1.1).
It did, however, give me the option of ignoring this warning and compiling with GCC 4.1.2.
I did ignore the warning and have not had any problems.
I'm just wondering is this why virtualbox keeps asking you to install the compiler when you already have GCC 4.1.2 installed.
Is it looking for GCC 4.1.1 and is not prepared to compromise?
If this is the case, I'm not too sure what you can do.
Edit: Maybe you could enquire about this point on the virtual box forum.
