I would advice for portable scripts to have their shebang adapted to point to the POSIX shell available on the target platform, e.g. on Solaris:
#!/bin/kshor even better for stricter...
Read MadeInGermany answer, aliases are simply not supported by the legacy Bourne shell which predates functions. There is no point trying to define and execute an alias under /sbin/sh or /bin/sh when...