Bug discovered in Forum v. 7.5

In this code something is wrong (file: functions/ functions_common.asp )

'*****************************
 '***** Internet Explorer *****
 '*****************************

 'See if MSIE is found in the user agent string then the broser is not a MAC or Opera pretending to be IE
 If InStr(1, strUserAgent, "MSIE", 1) AND InStr(1, strUserAgent, "MAC", 1) = 0 AND InStr(1, strUserAgent, "Opera", 1) = 0 Then

  'Now we know this is Windows IE we need to see if the version number is 5
  If Trim(Mid(strUserAgent, CInt(inStr(1, strUserAgent, "MSIE", 1)+5), 3)) = "5.0" Then

   RTEenabled = "winIE5"

  'Now we know this is Windows IE we need to see if the version number is above 5
  ElseIf Trim(Mid(strUserAgent, CInt(inStr(1, strUserAgent, "MSIE", 1)+5), 3)) => 5.5 Then

   RTEenabled = "winIE"

  'Else the IE version is below 5 so return na
  Else

   RTEenabled = "false"
  End If

In explorer 6 with SP1 the script failes when trying to post a new topic, file "post_message_form.asp" returns a blank page with source that says :

(quoted)
p>Microsoft VBScript runtime </font> <font face="Arial" size=2>error '800a000d'</font>
<p>
<font face="Arial" size=2>Type mismatch: '[string: &quot;6.0&quot;]'</font>
<p>
<font face="Arial" size=2>/forum/functions/functions_common.asp</font> ..

(/quoted)

The line reference is marked with bold red.
Any suggestions?