I tried to install python with make install DESTDIR=/home/blah 
./python -E ./setup.py install \ 
                --prefix=/ \ 
                --install-scripts=//bin \ 
                --install-platlib=//lib/python2.6/lib-dynload \ 
                --root=//home/blah 
running install 
running build 
running build_ext 
INFO: Can't locate Tcl/Tk libs and/or headers 
Failed to find the necessary bits to build these modules: 
_tkinter           bsddb185           dl 
imageop            sunaudiodev 
To find the necessary bits, look in setup.py in detect_modules() for 
the module's name. 
running build_scripts 
running install_lib 
creating /lib/python2.6 
error: could not create '/lib/python2.6': Permission denied 
make: *** [sharedinstall] Error 1 

I asked for help on the mailing list http://groups.google.com/group/comp.lang.python/browse_thread/thread/a0b0e49f7b8153d1#, and according to Martin v. Loewis  	
"If you have / as the prefix, you get two leading slashes, e.g. for 
//lib/python2.x. Any other prefix would have given you only a single 
slash: e.g. if it had been /usr, then you end up with /usr/lib/python2.x. 
Now, the code strips the first character to make it a relative path name 
(so that join can be used), which fails to work correctly if there are 
two leading slashes. "

I have attached the patch provided by him.