This artifact originates from the Orbit Project at Eclipse, it is an osgi bundle and is signed as well.
'org.eclipse.jetty.orbit:javax.servlet.jsp:2.1.0.v201105211820'
<dependency>
<groupId>org.eclipse.jetty.orbit</groupId>
<artifactId>javax.servlet.jsp</artifactId>
<version>2.1.0.v201105211820</version>
</dependency>
<dependency org="org.eclipse.jetty.orbit" name="javax.servlet.jsp" rev="2.1.0.v201105211820"/>
"org.eclipse.jetty.orbit", "javax.servlet.jsp", "2.1.0.v201105211820"