User Agent in W3C Extended Log File

I noticed that the User-Agent field in W3C Extended Log File is not fixed. (as shown below) 

Eg 1: Mozilla/4.0+(compatible;+MSIE+5.5;+AOL+6.0;+Windows+98) 
Eg 2: Mozilla/4.0+(compatible;+MSIE+5.5;+Windows+98;+Win+9x+4.90;+MSIECrawler)

Example 1 has 4 parts of information logged, separated by semicolon ";" whereas in example 2, there are 5 parts of information logged. I was wondering if there is a way to fix or standardized the logging format. I would greatly appreciate your suggesstion and comments.


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Received on Saturday, 1 December 2001 13:55:40 UTC