Firebird 2.5.0 RC2

* Administrative Enhancements

- System audit tracing and user trace sessions via the Services API, making it possible to monitor and analyse everything going on in a database in real time
- New system role RDB$ADMIN in the ODS 11.2 database allows SYSDBA to transfer its privileges to another user on a per-database basis
- More information in the monitoring tables
- Asynchronous cancellation of connections
- Capability for ordinary users to monitor any of their own attachments as well as CURRENT_CONNECTION

* Other SQL Language Additions and Enhancements
- Regular expression support using the SIMILAR TO predicate
- ALTER COLUMN for computed columns
- Autonomous transactions within a PSQL module (stored procedure, trigger or dynamically executable PSQL block)
- Enhanced access to stored procedures in view definitions
- Optional GRANTED BY or GRANTED AS for GRANT and REVOKE statements, enabling the grantor to be a user other than the CURRENT_USER (the default).
- REVOKE ALL syntax to dispose of all privileges for a user or role at once
- Support for WHERE SOME_COL = ? OR ? IS NULL predications
- Removal of “reserved” status for all but a handful of keywords that are not reserved in the SQL standard

* Data-handling Enhancements
- New built-in functions for converting UUID CHAR(16) OCTETS strings to RFC4122-compliant format and vice versa
- Ability to pass 32-bit and 64-bit integers as hexadecimal in numeric literal and X-prefixed binary string literal formats

* API Additions
- Statements now return an SQL-2003 standard 5-alphanumeric SQLSTATE completion code
- New constant DSQL_unprepare available for use with isc_dsql_free_statement for efficient unpreparing of statements

* International Language Support
- Default COLLATE clause for CREATE DATABASE
- Ability to change the default COLLATE for a used character set
- GBAK restore switches FIX_FSS_DATA and FIX_FSS_METADATA to restore legacy databases with UNICODE_FSS data and/or metadata correctly without resorting to scripts and manual techniques
- Accent-insensitive collation for Unicode