General :: $LD_LIBRARY_PATH Get Unset When Using Screen With Bash?

This is related to http://superuser.com/questions/27376/why-does-my-ld-library-path-get-unset-launching-terminal, but a different set of symptoms.First, /usr/bin/screen is setuid as per the other question. Second, the default shell on this system is /bin/tcsh for various historical reasons, and we're not allowed to chsh to /bin/bash, so I typically run bash manually immediately after login. Third, I almost always use screen, but I want ctrl-a ctrl-c in screen to create a new bash "tab", so I always invoke bash first.

That is:
{~} $ echo $SHELL
/bin/tcsh

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