为什么SQLite在使用Perl的DBD::SQLite时为事务中的第二个查询提供“数据库被锁定”?

Is there a known problem with SQLite giving a "database is locked" error for a second query in a single transaction when using Perl DBD::SQLite? Scenario: Linux, Perl DBI, AutoCommit => 0, a subroutine with two code blocks (using the blocks to localize variable names). In the first code block a query handle is created by prepare() on a select statement, it is executed() and the block closed. The second code block another query handle is created by prepare for an update statement, and frequently (30% of the time) SQLite/DBI gives a database locked error at this stage. I think the error happens during prepare() and not during the execute(). Is there a known problem with SQLite giving a "