How to clean a failed package to build?

[Kyunghoon Lee]

Hello all,

I was trying to build pang with a quartz option and it failed because of 
the option.  I wanted to rebuild pango w/o the quartz option, but port 
kept using the same variants option.  I tried to clean, but it seems 
"port clean" works only for successfully installed packages.  I'd 
appreciate it if someone help me clean the unsuccessful install process 
so that I can build pango as if I'm building it for the first time.  
Thank you in adv.