Steve, I thought it would be a good idea to move our discussion from the hibernate list here.

To summarize allowing 'ddl in tran' for tempdb database fixes some hibernate tests. According to the sybase manual it is not good to have it enabled as it leads to locking system tables during such a transaction. So they recommend to not use if possible or only in short transactions.
Thus I think it should be disabled for sybase at all.

According to your mail:
"I would guess that this because of temp tables. Hibernate allows the
Dialect to say whether or not the database supports DDL statements
within a transaction. Sybase does not override this; the default is to
query the JDBC metadata to see whether DDL is allowed within
transactions (see links below). My guess is that Sybase simply does not
report this accurately based on whether this option you mention is set
or not set; it probably just blindly says "yeah, we support it...". We
can look at changing this behavior for Sybase."

Let us know what do you think.

Thanks,
Aleksandar