My take on POJOs is that they are no longer POJOs when there is an import statement for something not conforming to the expression "java*.*".
I see quite a lot of frameworks and toolkits claiming benefits around POJO oriented development. However either through annotations, extension, implementation etc. they require dependencies on non JRE artifacts.
This situation is quite OK of course; I just think that it is useful to distinguish a POJO from its dependent form. For example if you're looking for Object Relational Mapping then you might want to consider the Java Persistence API instead of being directly dependent on an implementation; such as Hibernate. Maintaining this distinction allows you to consider migration strategies to other implementations if required.
Sometimes you need to be dependent on a toolkit or framework and that is of course perfectly acceptable. Being aware is the significant point.