In this presentation I will show my preliminary results from a research project about collaborative language learning in an academic online course in German. The study is based on a sample of 35 chat-logs from 30 students of different language background (Swedish or German as L1) and different levels of German proficiency, working on collaborative tasks in equal and unequal formations of triads or dyads. The data was collected in four of eight online seminars which were an obligatory part of a German literature course at a Swedish university. These seminars were conducted in private chat-rooms in MSN/Adobe connect. The students had to answer open-ended questions about the literature they had read, which they had prepared in advance. The results indicate that Swedish students with a lower level of German proficiency produce longer messages when interacting in formations with native speakers than with peers. On the other hand, interactional modifications or scaffolding where the attention was directed on form or meaning of the L2 overall occurred only to a small extend. This means that learners only get few opportunities to develop new L2 knowledge with the help of experts, a condition which is thought essential by researchers within a cognitive or sociocultural learning approach. Further study of the data reveals that the students frequently make use of imitation of whole utterances or parts of utterances of their collocutors. This strategy may help them to become more fluent in German and may also assist the development of more complex structures of the L2.