Here is a brief summary of changes made to these gff files.

08-02-2007 - Initial release as part of FB2007_01.

08-09-2007 - Added annotated repeat region features.  You can find
             them by looking for features with a source of DHGP.

           - Removed orthologous features that weren't obsoleted themselves
             but which were anchored to obsoleted chromosomes.  These
             were present in the dmel-all-r5.2.gff file but not the individual
             chromosome GFF files.  The obsoleted chromosomes can be identified
             by a _r4 appended to their name (e.g. 3R_r4).

           - Added GFF header and FASTA sequence to the dmel-all-r5.2.gff file.

08-20-2007 - Corrected a problem with a parent/child relationship that spanned
             multiple arms and broke the GFF feature inheritance model when split
             into individual files.  We now split the top level parent and make a
             new parent feature in both arms.  The parent reference in the
             children are also adjusted accordingly.

	     There was only one feature that had this problem.  Its ID was
             BATZ_Contrast:CG_BATZ_CON_47008285_caf1.

	   - Corrected a problem with FBti0077406 on chromosome 4.  This insertion
             was localized to 4 but had no coordinates, which caused problems with
             the GFF header formatting and subsequently invalidated the GFF format.
             This insertion has been removed from the GFF files and checks put in 
             place to prevent this in the future.