installing sage on sharcnet,

I've been trying to install sage on sharcnet for the past little while. There are few problems that come up when I try doing that, and I'm storing the experience here, in case I succeed, I can try it again.

• sharcnet uses pathscale as the default compiler, and it is recommended to me to compile using pathscale. pathscale has version 2.x.x, which is less than gcc 4.1.x that sage recommends. As result, I have to edit prereq-0.7/configure to get rid of it. (To install prereq, one should run {}/base/prereq-0.7-install)
• I need to have CFLAGS, CXXFLAGS, FCFLAG set, otherwise SAGE decides to set them to bunch of flags that causes problem on pathscale.
• after prereq, the next problem shows up in termcap. The -D flag for cc and gcc seem to be different. (This might be sharcnet preprocessing things.) Getting rid of the (unnecessary) offending -D flag makes it work. While making a patch, I notice that CFLAG is just over ridden. I'm changing that.