commit within function

Is there a way to issue a commit within a function and continue processing? I know this is not possible in 8.1..

We have long running function calls...parts of which are independent of each other. The independent functions are called within a "main" outer function. We would like to commit the data modified by each function as a single unit so that the data is freed up for other modules to act on.

Are there any future postgres releases (we use 8.1.9) that possible address this.