error message and documentation

Hi all, I use PostgresSQL 8.3 through JDBC
Recently one transaction has failed with the following error message:

Detail: Process 10660 waits for AccessShareLock on relation 36036 of
database 34187; blocked by process 2212.
Process 2212 waits for AccessExclusiveLock on relation 36044 of database
34187; blocked by process 10660.

I'm trying to understand why I can have this kind or error (it is
probably some programming mistake) but reading the PostgresSQL manual I
cannot find any trace of AccessExclusiveLock , while I have found
explanation of what AccessShareLock is.
First question: is there a problem in the documentation or in
PostgresSQL error messages ?

Another question. The message above was reported to explain why a query
sent to the db server has failed: am I right saying that, looking at the
above error message, Process 10660 was the one executing the query that
has failed and Process 2212 was executing something else and kept going
its way ?

Final question: is there a way to know what query a Process has executed
? I'm thinking of some logging configuration for PostgresSQL.

TIA to all of you.

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