Thank you very much for your answer!
Sorry for the formatting, I wrote it before I went to sleep. I will try to format this time better.

I use the sdk from here (https://www.novell.com/developer/dev..._sentinel.html) and my modified apache agent utility has the following modification:
/usr/bin/tail -F $(date +"%m%d"WAS.*) |\
awk -F',' '{print($0); fflush()}' |\
socat -u - $SOCAT_OPTIONS

With this I can transfer the webaccess logfile. The logfile looks like the following:
10:49:06, <SOAP>, -, INFO, username, Login
10:49:06, <SOAP>, -, INFO, username, Get Folder List

I created a new Collector (Novell, WebAccess, E-mail System) with Syslog Match Rule: SOAP.

When I used the collector I got the following error message:
Parsing failed: TypeError: Cannot call method "search" of undefined; input: 10:49:06, <SOAP>, -, INFO, username, Login

First I only commented out where the search was used, then I got the following error message:
Parsing failed: JavaException: java.lang.NumberFormatException: For input string: "null", input: undefinied.
So I comment out the whole content of the (this.CONNECTION_METHOD == "SYSLOG" && this.CONNECTION_MODE == "map") in the Record.prototype.preParse.

My parse:
Record.prototype.parse = function(e){
// parsing logic goes here

/INFO, (\S+),/.exec(this.s_RXBufferString);
rec.dun=RegExp.$1;
instance.SEND_EVENT = true;
return true;
};

In the Rec2Evt.map:
TargetUserName,dun

Now it is working also with this.dun.