Fetchmail and mail retrieval problem

[Aldo]

Hi,

for some reasons I use some .fetchmailrc-MMM conf files with the option
to keep mail on server.

It works for many of my ISPs, just one doenst run correctly:
it takes mail from 1 to 10, then ten minutes later it gets again from 1
but this time until 16, and so on...
Can I fix this in the fetchmail rc conf, or is it only my ISP who should
fix this on their side (X-status param or so) ?

My .fetchmailrx-MMM contains simple traditional parameters:
poll pop.mmm.be with protocol POP3
	user uuu there has password ppp is aldo here and wants keep;

Any help is welcome!

Aldo.