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.
OGNL expressions look on the value stack. Scriptlet variables are not on the value stack. The *easiest* thing to do would be to put the scriptlet variable into a JEE scope (page or request, probably): OGNL expressions *can* access scoped variables.
Really, though, this is a Bad Idea, and there's almost *never* an absolute need to do this.