This is the new method of logging, and, when it works properly, would merge #mirc.dalnet.1 to #mirc.dalnet, then delete the #mirc.dalnet.1 until you were logging in that channel again.
The .1 log is always the log of your current session.
Since you have .2 and .3 logs, then the .1 log wasn't deleted after being merged (if it was merged) and mIRC noted this, making the original .1 log a .2, then later on, making tne .2 a .3, the .1 a .2, and your current session the .1
If you look at the #mirc.dalnet log, and compare the end of the log with what's in the .3 and/or .2 logs, you should be able to determine if they were merged or not. If they were, then you can just delete the .2 and/or .3 logs
This problem has been reported previously, and I believe Khaled has said that he will try to have it fixed for the next version, but as it seems to be inconsistant as to when it does/does not work properly, he may have a hard time ensuring that it is fixed for the next version.
Please note, that Khaled has stated that there are no plans to go back to the previous logging method (which is what it sounds like you're actually asking for, ie: one log file, rather than a current and a updated)
