dLibra is a software package for building complex and highly interoperable digital libraries, which is developed by Poznań Supercomputing and Networking Center since 1999. The increasing number of dLibra end-users and increasing variety of institutions exploiting dLibra is a source of new needs and challenges. One of such challenges comes from the differences in type and complexity of digital heritage objects published on-line by institutions coming from different domains. In the ideal situation each of the types of objects should have dedicated user interface, but on the other hand, as far as digital objects are concerned, the issues related with storage and management can be performed by one adequately unified system. In this paper we present the issues related with the development of digital libraries containing digital heritage objects coming from different domains and the solutions that we propose in the context of the dLibra software.