The paper presents our first work in progress results of an approach to verify the correct use of software libraries in target projects. Therefor the project's source code is analyzed and checked against the library's behavior specification, called interface grammar. This grammar is formalized using annotated state diagrams, and the verification analysis is based on static control flow, data flow and alias analyses. The paper illustrates the presented approach using a small-sized Java library example. In the end, we give a brief outlook to necessary enhancements.