Description of problem:
Response time metrics are not being read from the IIS VHost log file due to what appears to be a file offset issue. The agent log contains the following:

INFO  [ResourceContainer.invoker.daemon-2] (org.rhq.plugins.iis.IISResponseTimeDelegate$IISResponseTimeLogParser)- Filesize 702
INFO  [ResourceContainer.invoker.daemon-2] (org.rhq.plugins.iis.IISResponseTimeDelegate$IISResponseTimeLogParser)- Skipping 702
INFO  [ResourceContainer.invoker.daemon-2] (org.rhq.plugins.iis.IISResponseTimeDelegate$IISResponseTimeLogParser)- Results...

Which seems to indicate that previousOffset is always equal to newOffset. The result is not log information appears to be parsed.

Version-Release number of selected component (if applicable):
4.4.0.JON311GA

How reproducible:
Always

Additional info:
Details from the support engineering who did the preliminary investigation:

Checking the IISResponseTimeDelegate class again, I realized that the "parsing" was not being done because the currentLine variable is coming as "null". I think it happens due the Filesize and Skipping have the same value (as we can see in the debug messages above), then the "in" variable is set to "null" or "0" (not sure). Follow a snippet of the code: 
__________________________________________________________________

* parseLog method in IISResponseTimeDelegate class:

 log.info("Filesize " + newOffset);
 log.info("Skipping " + previousOffset);
 in.skip(IISResponseTimeDelegate.this.previousOffset);
 IISResponseTimeDelegate.this.previousOffset = newOffset;

 String currentLine;
 while ((currentLine = in.readLine()) != null) {
    LogEntry logEntry;
    log.info("Parsing line: " + currentLine);
    try {
       logEntry = parseLine(currentLine);
__________________________________________________________________

I performed another test commenting the in.skip... line, then the CallTime was collected correctly.