Christian,
If these are all JAR libraries creating User Libraries that you add to the build paths of all these projects is the best way to go. Just be sure in your projects to tell MyEclipse to deploy your User Libraries and you should be all set.
The only heads up I would say is that currently taglib resolution from user libraries is not working so you will get a lot of “tag undefined” warnings in your JSP pages. This is a bug that we hope to address in MyEclipse 5.0 as it is very frustrating and we appologize for that.