How to stop files auto-prompting in irb?

Hi all,
I installed ruby182-14_RC8a (for Windows) just now. I find irb will
auto-complete keywords when I type TAB key. I modify irb.bat to disable
this feature:
"c:\ruby\bin\ruby.exe" "c:\ruby\bin\irb" --noreadline %1 %2 %3 %4 %5 %6
%7 %8 %9
But irb still prompt current filenames by TAB. How to stop it?
(I often copy codes containing TABs into irb directly, so this feature
will mess up screen.)

Thanks a lot!

X.Y. Yang