As I wrote last week to debian-devel@l.d.o I started the again a mass bug filling against all packages which fails to build twice and three times in a row. Furthermore we checked this time if the package content has changed between the builds.
Today I completed these bug reports finally :). I wrote today about ~400 bug reports against several packages. Some packages which are very well known are:
- aptitude
- php5
- debian-policy (my favourite ;-))
- ...
All failures concering doublebuild or three time build issues
are filled with Severity: Important and all bugs against packages
which have a different content after the builds are filled with
Severity: Serious. Please fix all of them as soon as possible 
(To fix this issues is a release goal for lenny ;-))