Control: notfound -1 1:1.5.2-2 Control: notfound -1 1:1.5.1-2 Technically the missing epochs are also in stable, but since there were no new symbols add in 1.5.2 this is not a problem when upgrading from 1.5.1 in oldstable.
The package in oldstable is not affected by chance since dpkg-gensymbols: warning: some new symbols appeared in the symbols file: see diff output below happens to do the right thing. cu Adrian
