Crash on delaying input

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Entering a longer function, such as x^2-x^4
2. entering the - will crash the engine when attempting to draw the invalid 
function.

What is the expected output? What do you see instead?
No output yet.  The machine crashes when attempting to draw the incomplete 
function.

What version of the product are you using? On what operating system?
version of Nov 2009.  Android 2.1 on Samsung Anycall

Please provide any additional information below.

Original issue reported on code.google.com by melchi...@gmail.com on 2 Oct 2010 at 5:06