Set delay to show up alternative letters (äöüéèìá etc)

[OlDirty]

I have been searching nearly the whole www (i feel like i did) for a solution to set a shorter delay for the iPhone keyboard to show alternative letters after long-pressing any standard letter. While typing quite fast it´s annoying to wait "1 second" to write one of these (in germany called umlaute). Particularly you often make use of them in the german language.

I´m running a 3Gs with iOS 4.3.3, jailbroken and unlocked.