Why does GHC replace implicit tabs by spaces

Hi everybody! I am a bit surprised that GHC replaces " Hallo" (I used a tab here - used not coded ('\t').) by " Hallo". (GHC replaced the tab by 8 spaces.) Is this a bug? Hugs keeps the tab. (See the attached code, and output from Hugs and GHC. I am using ghc-5.04 and WinNT.) Any comments? Andreas