As per https://issues.apache.org/jira/browse/INFRA-5910 the PEAR release packages were faulty.
I rebuilt them for 0.4 and also created a 0.5 PEAR release from the 0.5 tag in svn. I had to alter the package.xml slightly in order to fix both but there was also a problem with the packaging system on the pear.a.o host so I rebuilt them locally, uploaded and then registered them to the channel from there. I tested all the rebuilt 0.4 and 0.5 releases on pear.a.o with ''pear install oodt/Apache_OODT/$package'' and all installed without any problems for me. Please check and test and see if the same is true for you too. I'll prepare the trunk package.xml files for the next release iteration tomorrow. Thanks Gav...