Migration step with create_table with string column with :default => "" fails due to missing default value in SQL

A test case is attached to this issue.

[uwe@pippin activerecord-jdbc]$ rake test_derby
(in /home/uwe/workspace/aifudis/activerecord-jdbc)
You really need Hoe installed to be able to package this gem
Loaded suite /usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake/rake_test_loader
Started
....E.................
Finished in 6.455585 seconds.

1) Error:
test_create_table_column_quoting_vs_keywords(DerbyQuotingTest):
ActiveRecord::StatementInvalid: ActiveRecord::ActiveRecordError: Syntax error: Encountered "NOT" at line 1, column 114.: CREATE TABLE dummies (id int generated by default as identity NOT NULL PRIMARY KEY, "year" varchar(256) DEFAULT NOT NULL)
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/connection_adapters/abstract_adapter.rb:147:in `log'
/home/uwe/workspace/aifudis/activerecord-jdbc/lib/active_record/connection_adapters/jdbc_adapter.rb:537:in `execute'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/connection_adapters/abstract/schema_statements.rb:108:in `create_table'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:346:in `method_missing'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:326:in `say_with_time'
/usr/local/jruby-1.1.4/lib/ruby/1.8/benchmark.rb:293:in `measure'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:326:in `say_with_time'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:342:in `method_missing'
/home/uwe/workspace/aifudis/activerecord-jdbc/./test/derby_migration_test.rb:6:in `up'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:280:in `migrate'
/usr/local/jruby-1.1.4/lib/ruby/1.8/benchmark.rb:293:in `measure'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:280:in `migrate'
/usr/local/jruby-1.1.4/lib/ruby/gems/1.8/gems/activerecord-2.1.1/lib/active_record/migration.rb:263:in `up_with_benchmarks'
/home/uwe/workspace/aifudis/activerecord-jdbc/./test/derby_migration_test.rb:18:in `test_create_table_column_quoting_vs_keywords'

22 tests, 34 assertions, 0 failures, 1 errors
rake aborted!
Command failed with status (1): [/usr/local/jruby-1.1.4/bin/jruby -Ilib:tes...]

(See full trace by running task with --trace)
[uwe@pippin activerecord-jdbc]$