Error is getting displayed in OWA 2003

Hi all,
I am using OWA 2003 to acess my company mails.When i open home page it looks like this https://webmail.company.com/exchweb/bin/auth/owalogon.asp?url=https://webmail.company.com/exchange&reason=0 , when i change ‘reason=0’ to any value like ‘reason=’ ( replace 0 with blank, it shows the following error)

Microsoft VBScript runtime error ‘800a000d’

Type mismatch: ‘[string: “”]’

/exchweb/bin/auth/USA/logon.asp, line 527

Why it is happening and let me know the solution for this. As this is microsoft product can i rectify it from my side.

Please let me know abut this issue.

Thanks

mindsec