Over this weekend I decided to download the Android source tree on my computer (Backtrack 4 R2). The BT4R2 is no longer supported by the Offsec/Backtrack guys (mutt, purehate, etc.).
To start off with I tried to follow the instructions listed here.
The first error I got was with Git, I was using a version earlier than 1.5.4. So I downloaded git version 1.7.4, compiled it and installed it. Then I got the error:
fatal: unable to find remote handler for 'https'
Too bad, I tried recompiling and what not, and I did have openssl…so what was the problem?
The problem was not having libcurl-devel library. So I downloaded the library and launched configure, make clean, make and make install to reinstall git. Now the error was gone.

On the step where I am supposed to execute the following:
$ repo init -u https://android.googlesource.com/platform/manifest
I got the following error:

Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
self.run()
File "/usr/lib/python2.5/threading.py", line 446, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/user/bin/.repo/repo/subcmds/sync.py", line 182, in _FetchHelper
success = project.Sync_NetworkHalf(quiet=opt.quiet)
File "/home/user/bin/.repo/repo/project.py", line 926, in Sync_NetworkHalf
if alt_dir is None and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/user/bin/.repo/repo/project.py", line 1444, in _ApplyCloneBundle
exist_dst = self._FetchBundle(bundle_url, bundle_tmp, bundle_dst, quiet)
File "/home/user/bin/.repo/repo/project.py", line 1514, in _FetchBundle
size = r.headers['content-length']
File "/usr/lib/python2.5/rfc822.py", line 384, in __getitem__
return self.dict[name.lower()]
KeyError: 'content-length'
Exception in thread Thread-3:
Traceback (most recent call last):
File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
self.run()
File "/usr/lib/python2.5/threading.py", line 446, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/user/bin/.repo/repo/subcmds/sync.py", line 182, in _FetchHelper
success = project.Sync_NetworkHalf(quiet=opt.quiet)
File "/home/user/bin/.repo/repo/project.py", line 926, in Sync_NetworkHalf
if alt_dir is None and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/user/bin/.repo/repo/project.py", line 1444, in _ApplyCloneBundle
exist_dst = self._FetchBundle(bundle_url, bundle_tmp, bundle_dst, quiet)
File "/home/user/bin/.repo/repo/project.py", line 1514, in _FetchBundle
size = r.headers['content-length']
File "/usr/lib/python2.5/rfc822.py", line 384, in __getitem__
return self.dict[name.lower()]
KeyError: 'content-length'
Exception in thread Thread-4:
Traceback (most recent call last):
File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
self.run()
File "/usr/lib/python2.5/threading.py", line 446, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/user/bin/.repo/repo/subcmds/sync.py", line 182, in _FetchHelper
success = project.Sync_NetworkHalf(quiet=opt.quiet)
File "/home/user/bin/.repo/repo/project.py", line 926, in Sync_NetworkHalf
if alt_dir is None and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/user/bin/.repo/repo/project.py", line 1444, in _ApplyCloneBundle
exist_dst = self._FetchBundle(bundle_url, bundle_tmp, bundle_dst, quiet)
File "/home/user/bin/.repo/repo/project.py", line 1514, in _FetchBundle
size = r.headers['content-length']
File "/usr/lib/python2.5/rfc822.py", line 384, in __getitem__
return self.dict[name.lower()]
KeyError: 'content-length'
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
self.run()
File "/usr/lib/python2.5/threading.py", line 446, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/user/bin/.repo/repo/subcmds/sync.py", line 182, in _FetchHelper
success = project.Sync_NetworkHalf(quiet=opt.quiet)
File "/home/user/bin/.repo/repo/project.py", line 926, in Sync_NetworkHalf
if alt_dir is None and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/user/bin/.repo/repo/project.py", line 1444, in _ApplyCloneBundle
exist_dst = self._FetchBundle(bundle_url, bundle_tmp, bundle_dst, quiet)
File "/home/user/bin/.repo/repo/project.py", line 1514, in _FetchBundle
size = r.headers['content-length']
File "/usr/lib/python2.5/rfc822.py", line 384, in __getitem__
return self.dict[name.lower()]
KeyError: 'content-length'
Exception in thread Thread-5:
Traceback (most recent call last):
File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
self.run()
File "/usr/lib/python2.5/threading.py", line 446, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/user/bin/.repo/repo/subcmds/sync.py", line 182, in _FetchHelper
success = project.Sync_NetworkHalf(quiet=opt.quiet)
File "/home/user/bin/.repo/repo/project.py", line 926, in Sync_NetworkHalf
if alt_dir is None and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/user/bin/.repo/repo/project.py", line 1444, in _ApplyCloneBundle
exist_dst = self._FetchBundle(bundle_url, bundle_tmp, bundle_dst, quiet)
File "/home/user/bin/.repo/repo/project.py", line 1514, in _FetchBundle
size = r.headers['content-length']
File "/usr/lib/python2.5/rfc822.py", line 384, in __getitem__
return self.dict[name.lower()]
KeyError: 'content-length'
error: Exited sync due to fetch errors

Seems like this error is caused because the content-length http header is not sent by the repository. If you upgrade to Python 2.7.x you can resolve this error.
Now if you are compiling Python from source, it doesn’t come by default with SSL support. So to add SSL support you should edit the Python-2.7/Modules/Setup file and uncomment four lines:
_socket socketmodule.c
# Socket module helper for SSL support; you must comment out the other
# socket line above, and possibly edit the SSL variable:
SSL=/usr
_ssl _ssl.c \
-DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
-L$(SSL)/lib -lssl -lcrypto

Of course, then you can do the standard steps to compile and install python:
$ ./configure
$ make
$ sudo make install

repo sync would work very well thereafter.