This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
That means you are defining two different functions for two different methods in the same class, this is perfectly valid in the tld. The <name> component must be unique in the tld, but you can use same class and signature in the two <function> element, to define the different name to use in EL.
Also you can not place multiple entries of <function-class> and <function-signature> under <function> element.