You can some additional dependencies to the javadoc classpath.
For instance, with the following configuration:
<project> ... <reporting> (or <build>) <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-javadoc-plugin</artifactId> <version>2.10.4</version> <configuration> ... <additionalDependencies> <additionalDependency> <groupId>geronimo-spec</groupId> <artifactId>geronimo-spec-jta</artifactId> <version>1.0.1B-rc4</version> </additionalDependency> </additionalDependencies> ... </configuration> </plugin> </plugins> ... </reporting> (or </build>) ... </project>