I'm sorry, but that just doesn't work. If it was that easy it would have worked when Calc opened the Excel spreadsheet. It returns #VALUE! Just to be sure it wasn't because it was sourced from Excel, I tried it in a new empty Calc worksheet, and it's the same error: abc (cntl-enter) ef gh (cntl-enter) ijk in cell A1, =search(char(10);a1;1) in b1 displays #VALUE!. This happens in both Linux and Windows versions. As an additional test, copy the string in a1 down through multiple cells, and enter the formula =CODE(MID(A1;ROW();1)) in b1 and copy it down too. The code for (cntl-enter) is 32, the same as a space. Since this is obviously wrong, there must be some other trick. Or it is something that Calc is just not capable of doing.
OpenOffice 3.1 on Windows XP and Slackware64 13