Patterns of students' language learning were examined through an asynchronous cross-cultural bilingual communication project conducted between Japanese university students learning English and Canadian university students learning Japanese. Previous studies on cross-cultural communication projects have reported positive outcomes in providing learners with opportunities for cultural and language learning. However, very few, if any, investigated whether a meaning-focused communication project like ours provides similar opportunities for language learning, and if so, what kind of language learning takes place. With focus on Canadian students' learning of Japanese, the present study addressed these questions through analyses of students' logs and message texts. The results indicated that students have opportunities for all aspects of language learning, including vocabulary, kanji, grammar, and phrase/sentential expressions. However, it was also found that the amount and type of incidental learning may depend on the students' proficiency level. Explicit corrections are noticed but often not understood unless clear explanations are given. We suggest these kinds of communication projects might further promote incidental learning opportunities by better understanding the proficiency levels of the other's second language, as well as by more and better incorporation of clear error corrections possibly accompanied by metalinguistic explanations. (Contains 4 tables.)