Internationalized Domain Name toolkit 2 (idnkit-2)
Internationalized Domain Name toolkit 2 (idnkit-2) provides useful APIs (libraries) for application developers to make softwares IDNA2008-compliant, and also provides tools for system administrators to process IDNs appropriately according to IDNA2008 specification. The idnkit-2 is a toolkit revised by JPRS from the idnkit-1.0 developed by JPNIC, and it is released as an open source free software modified to comply with IDNA2008.
I need to investigate this, as it may let me replace the work I’ve done myself on IDNA support with something with wider support.