JSESSIONID's with null or empty values

Hi Chris,

I've updated your second example to streamline it a bit and add comments. The reason this approach works for null cookie values is that HTTP::cookie value "cookie_name" will return nothing if the cookie is not present or has a null value.

when HTTP_REQUEST {
    Check if the JSESSIONID cookie is present in the request and has a non-null value
   if { [HTTP::cookie "JSESSIONID"] ne "" }{
       Persist on the JSESSIONID cookie value for X seconds
      persist uie [HTTP::cookie "JSESSIONID"] 2700
   } else {
       Cookie wasn't set or didn't have a value, so check for the session ID in the URI
      set jsess [findstr [HTTP::uri] "JSESSIONID" 11 ";"]
      if { $jsess != "" } {
          Persist on the JSESSIONID URI value for X seconds
         persist uie $jsess 2700
      }
   }
}
when HTTP_RESPONSE {
    Check if the JSESSIONID cookie is present in the response and has a non-null value
   if { [HTTP::cookie "JSESSIONID"] ne "" }{
       Persist on the JSESSIONID cookie value for X seconds
      persist add uie [HTTP::cookie "JSESSIONID"] 2700
   }
}

Aaron