diff --git a/easybuild/easyblocks/t/trinity.py b/easybuild/easyblocks/t/trinity.py
index 5931284cd7..ebf9c3a270 100644
--- a/easybuild/easyblocks/t/trinity.py
+++ b/easybuild/easyblocks/t/trinity.py
@@ -43,6 +43,7 @@
 from easybuild.framework.easyblock import EasyBlock
 from easybuild.framework.easyconfig import CUSTOM
 from easybuild.tools.build_log import EasyBuildError
+from easybuild.tools.environment import setvar
 from easybuild.tools.filetools import apply_regex_substitutions
 from easybuild.tools.modules import get_software_root
 from easybuild.tools.run import run_cmd
@@ -72,6 +73,8 @@ def butterfly(self):
 
         self.log.info("Begin Butterfly")
 
+        setvar("JAVA_TOOL_OPTIONS", "-Dfile.encoding=UTF8")
+
         dst = os.path.join(self.cfg['start_dir'], 'Butterfly', 'src')
         try:
             os.chdir(dst)