You could associate both package names with the same symbol table. 
package New::MyModule;

*Old::MyModule:: = \*New::MyModule::;

...

1;

[download]

Update: Added missing trailing colons. Tested: 

use strict;
use warnings;

BEGIN {
   package New::MyModule;

   *Old::MyModule:: = \*New::MyModule::;

   sub foo { print @_ }

   1;
}

New::MyModule::foo("new\n");
Old::MyModule::foo("old\n");

[download]

In reply to Re: Rename/Relocate A Module by ikegami
in thread Rename/Relocate A Module by rajib_rashid

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