This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
It's rare to need such init parameters in a JSP that's properly focused on view generation, so such a capability was not added to the EL. If you really need them (and you're being careful not to be using the JSP for purposes for which it should not be used), you can grab the init params in the controller and pass them to the JSP as scoped variables.
Or, write a nice little custom tag that does it for you.