Redmine

Dear All,

My use of Redmine would be eased if i could upload a CSV file with new "due date" for many issues.
For now i never enter into Redmine Customisation so i don't know what should be done :

- use the technology i know (i'm new in RoR world) to directly do it with SQL (even through a PHP code) : with insert into hostory tables and change into the issue table.
- use ready made function from RedMine application in a Redmine Plugin (i give the new "due date" and it automatically set the history data ...)

If the second solution is possible, is there anyone that can explain how i will find such functions ?

Thanks in advance.

Guillaume