Well, the August 3rd nightly was based on SVN revision 4346, so the best way to ensure compatibility is to download that specific source revision:
svn co svn://svn.berlios.de/codeblocks/trunk -r 4346
(Or, if using TortoiseSVN, just use 4346 instead of the HEAD revision.)
You can basically use your nightly build to build an almost-identical version from these new sources, then rebuild your plugin to link to this just-built version.