I've run into this problem on step 26 of installation:
<i>ERROR 2006-11-25 22:58:29
CJS-20019 Error when installing temporary license. DIAGNOSIS: External systems are not available. SOLUTION: Check connection to DB and messaging service.
</i>
Once in a lifetime, the solution is the right one (it was for me at least): <b>I went to MMC and started my brand new J2E instance, then hit "Retry", and installation happily came to the end</b>.
Cheers,
Alex