To push further this idea, I have written directly to the communities of those projects, to advice them to develop a zimlet as an interface to their timesheet product.
What each of us could do to make this feature been developped is to do the same with each of the FOSS timesheet solutions find around, in order that the communities of those projects really feel the interest they may have to develop this zimlet.
So, I'm gonna write an email to this other timesheet product right now ! (thanks for the information Krabina !

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