s.linkTrackEvents value changing when s.tl() call happens

Hi.  I have an event based rule set up in DTM that needs to append a serialization string to an event.  To do this, I have tried this via the DTM UI as well as with custom Javascript within the rule.  In both cases I run into the same problem.  Basically, the value in s.linkTrackEvents is overwritten with a copy of what is in s.events.  So, for example, the variables going into the s.tl() call are:

s.events='event99:12345';

s.linkTrackVars='events';

s.linkTrackEvents='event99';

When the s.tl() call happens (with the debugger running), s.linkTrackEvents shows as: s.linkTrackEvents='event99:12345';

This also happens if I use the DTM UI to set the event and place a serialization value.

When s.linkTrackEvents includes the serialization value on the event, the event does not get set in the tracking call.  I've debugged the code, and the variables are all set correctly going into the s.tl() call.

One other piece of info, we are using a a different s object (s_dtm).

Thanks for any help.