Environment: Spring 2.0.8, c3p0 0.9.1.2
Issue: When initializing c3p0 via beans, it is not possible to set the value of a c3p0 configuration parameter to an empty string. c3p0 interpretes this as it would be an actual value.
Solution / CR: Make c3p0 configuration parameter handling more robust by treating an empty string "" as NULL.
Detail: the issue has even a higher impact as with Spring 2.0.8 it is not possible to configure PropertyPlaceholderConfigurer to convert empty string to null. As consequence, the only thing I can do at the moment is to drop support for certain c3p0 config params which would have NULL as default value in our application