[OT] How can I change Debian's default Python version?

[Franz GEIGER]

When I call the Python interpreter, the Python 2.4.1 version is called,
because I installed it weeks ago from source by myself. That means the
symlink /usr/bin/python points to 2.4. Fine.

Now, when I install Python packages using the convenient Synaptic Package
Manager, everything goes into the 2.3-directory-tree. How can I change
that?

Many thanks in advance and kind regards
Franz GEIGER