WLS does not handle reusable jar with tag-files?

Question

I want to encapsulate some tag-files in a re-usable jar that can be included in multiple applications. According to all the documentation that I've found what I need to do is create a jar file containing:
META-INF/taglib.tld
META-INF/tags/myTag.tag
where the taglib.tld contains (among other things):
<uri>myTag</uri>
<tag-file>
<name>someName</name>
<path>META-INF/tags/myTag.tag</path>
</tag-file>
Then I am supposed to take that jar file and put it in my web application under WEB-INF/lib,
and in my index.jsp I can refer to <%@taglib prefix="myt" uri="myTag">
However when I do this (on wls 12c) the application seems to deploy ok but when I try to access index.jsp I get:
weblogic.servlet.jsp.CompilationException: Failed to compile JSP /index.jsp
index.jsp:14:4: No tag library could be found with this URI. Possible causes could be that the URI is incorrect, or that there were errors during parsing of the .tld file.
<%@taglib prefix="tags" uri="myt" %>
Related facts:
1. When I deploy these projects in Glassfish it works . as I expected based on the documentation with no errors.
2. If I copy the tag files and tld with no modification directly into the web application as:
<my web app>/WEB-INF/taglib.tld
and <my web app>/META-INF/tags/myTag.tag
then it does work. However, that prevents me from packaging the tag-files as a re-usable jar.
(Facts 1 & 2 seem to imply that the files are correct and that WebLogic is not handling the jar correctly?)
3. I've seen suggestions that there needs to be a <taglib> entry in web.xml. I have tried this and...
- the text I've seen on the web generates an error. It seems to need to be within a <jsp-config> entry in web.xml.
- even with this I still get the same error.
Does anyone have a suggestion for how to get Weblogic to handle tag-files inside a re-usable jar?
Do you have an example jar you can point me to just to see that it works on my system?
Is there some special configuration needed by Weblogic to tell it to handle this construct?
And finally, the error message is saying that one of two things is wrong:
Either:
A) it cannot find the referenced taglib file, or
B) the tld file failed to compile.
Is there any way for me to find out which of these is happening? The error messages in WLS do not seem to give any more info, so I cannot easily distinguish between these possibilities.
Thanks for your assistance.

Answer 1

After 3 days of seeing this error, immediately after posting this request the problem disappeared. Sigh.
So for now this problem is closed. If it comes back I'll re-post.