BSP page error.

Hello Gurus,

    I just started working on BSP and I am trying to create a logon page for vendor side using BSP.I followed http://scn.sap.com/people/sergio.ferrari2/blog/2007/04/06/bsphowto--customizing-the-design-of-system-logon-page-in-netweaver-04

this thread.But while executing I am getting this error.

BSP Exception: Das Objekt default.htm in der URL /sap/bc/bsp/sap/zvendor_logon/default.htm?sap-client=120&sap-sessioncmd=open ist nicht gültig.

I am not able to understand this error.Many of you have got such kind of requirement.Can any one help me with better process step by step or with screen shots.Also can you please help me out to resolve this error.

Thanks

Gaurav Gautam