Context: Individuals' personality traits have been shown to influence their behavior during team work. In particular, positive group attitudes are said to be essential for distributed and global software development efforts where collaboration is critical to project success. Objective: Given this, we have sought to study the influence of global software practitioners' personality profiles from a psycholinguistic perspective. Method: Artifacts from ten teams were selected from the IBM Rational Jazz repository and mined. We employed social network analysis (SNA) techniques to identify and group practitioners into two clusters based on the numbers of messages they communicated, Top Members and Others, and used standard statistical techniques to assess practitioners' engagement in task changes associated with work items. We then performed psycholinguistic analysis on practitioners' messages using linguistic dimensions of the LIWC tool that had been previously correlated with the Big Five personality profiles. Results: For our sample of 146 practitioners, we found that the Top Members demonstrated more openness to experience than the Other practitioners. Additionally, practitioners involved in usability-related tasks were found to be highly extroverted, and coders were most neurotic and conscientious. Conclusion: High levels of organizational and inter-personal skills may be useful for those operating in distributed settings, and personality diversity is likely to boost team performance.