#7 bind problems

[Martin Drautzburg]

All bind variables are treated as varchars. AFAICS this
it due to a limitation of the DBD::Oracle. Now not even
sqlplus supportd DATE bind variables, so we may not be
much worse than sqlplus.

As a consequence some statements that run in plsql will
not run in senora. Especially EXPLAIN PLAN has problems
with typed (eg DATE) bind variables.

Again this problem also exists in native sqlplus