Italy: document sequencing is required to be by calendar year, but credit memos use prior year seq

Problem Description: In Italy, document sequencing is required to be sequential and gapless by calendar year. However, credit memos use the original transaction date and therefore may have prior year's sequence. Note, the CM's must use the ORIGINAL TRX_DATE of the ORIGINAL INV for tax calc purposes. The desired behavior is for CM's (and INV's) to use the appropriate sequence based upon the GL date of the trx, and not based upon the trx date of the INV or CM.
This is required by Italian law,

Please help!!

Regards,
Sri