I ran into the same problem when trying to run vmwarevSphereHealthCheck.pl from cron on a vma. It worked great from a shell, but not from cron evidently, instead I got the error:
Server version unavailable at 'https://<my_vscerver>:443/sdk/vimService.wsdl' at /usr/lib/perl5/5.10.0/VMware/VICommon.pm line 545.
I fixed it by including the .profile to set the environment variables properly, like this:
0 0 * * * . /home/vi-admin/.profile ; /home/vi-admin/bin/vmwarevSphereHealthCheck.pl --conf /home/vi-admin/bin/healthCheck.conf --server <my_vcserver> --username <my_admin> --password <my_password> --type vcenter --email yes >/home/vi-admin/logs/healthCheck.log 2>&1
I hope this helps.