Log file rotation isn't working properly

[alahiff]

We have multiple files:

root@imc01:~# ls /var/log/imc
imc.log  imc.log.1  imc.log.10  imc.log.2  imc.log.3  imc.log.4  imc.log.5  imc.log.6  imc.log.7  imc.log.8  imc.log.9

but the contents are duplicated across all the files more or less.