Unfortunately the datasheets are only available in a slightly 40bit scrambled version, which will take you some five days up to first being able to open it. But it's freely downloadable from http://www.nxp.com/acrobat/other/identification/mc073933.pdf.
In case you are looking trying to open a 40bit encrypted PDF that you have lost the key for, try searching for a key in block# 37635, many PDFs use that block to store the key.
An unencrypted older version is available from http://www.nxp.com/acrobat/other/identification/mc073930.pdf.
There's also a "short form specification" for the RC632 at http://www.nxp.com/acrobat/other/identification/SFS070632.pdf that's freely downloadable.
There is a public data sheet at http://www.nxp.com/documents/data_sheet/CLRC632.pdf (Rev. 3.5 — 10 November 2009)