From the Wikibooks page on Claude Martin 
Claude Martin claims that the Voynich Manuscript would contain a phoney text, based on numeric sequences transcribed into anagrams. For example, a line forged on sequence 345678 would be retranscribed into 643875. This "fill in text method" would be used to produce text having some semantic similarities with a real text.
His website, in French is 
There are various counter-arguments to this (even if 'the usual problems' with resolving anagrams are ignored for this purpose). It would require a considerable amount of time and work to generate the text of several hundred pages and in a form that resembles 'an ordinary written text' of the period (as well as the cost of the materials and the absence of surviving draft versions, which would have to exist).