Missing icons on buttons when displayed with PDA

Hi all,

I am developping an online application for my PDA by using WebDynpro. The application contains several buttons with icons. When running it on my PC everything is fine. But when the application is displayed in the InternetExplorer on my PDA the icons are missing and the tooltips too. Is'nt it possible to use buttons with icons at all on PDA or what else could be my mistake?

Thanks for help.

Sybille