Oracle error 1861 translates to: "Literals in the input must be the same length as literals in the format string". It's not usually an LEI error, but Oracle not liking the command in question.
IEI 9.0 and LEI 7 had very different requirements for the Oracle connector version. Was the Oracle Client upgraded along with LEI? If so, then something may have changed on the Oracle side. If not, then check and make sure your combination of LEI and the Oracle Client are still compatible. Check the 9.0.1 Release Notes, found here:
http://publibfp.dhe.ibm.com/epubs/pdf/i1329171.pdf
Failing that, consider rebuilding the connection and Command activity in LEI, just in case. But otherwise you may need to troubleshoot the procedure, and the input actually being presented to it. From the LEI side, enable the Oracle connector option to Output SQL Statements to Log. Set up Oracle Client tracing, see if the input is getting malformed en-route. Also see if there are any obvious problems or log messages on the Oracle side - there must be some reason why it doesn't like the input.