The following code doesn't crash: HSSFFormulaParser.parse("B0", wb); (It actually returns a RefPtg of "B65536" in latest svn trunk). This is a regression from version 3.2, which seems to have occurred in early 3.5-beta versions. It was fixed by 3.5-beta4, but then re-regressed (junits didn't cover this case).
fixed in svn r781616 junits added