Test Cases with Multiple Issue Links

We have the need to import test cases that have links to more than one story in the project.  I have tried using ',' to separate the key values, I keep getting an error on the second issue key.

Test Case 1 relates to both Story-1 and Story-2 (below is what I want it to look like, but had to do manually after importing the test case).

Can this be done via the importer?  If so, what is the format to be used on the spreadsheet?