PHK's MD5 might not be slow enough anymore

[Roger]

What would be the consequence of having an algorithm that will
increase the amount of time needed to check the next password after a
failure.
In other words, check the first one fast, the second try it will be
slower, then the third even slower and then the forth even slower etc.
Is this how it is currently implemented? (Sorry I did not read the
code).

-r