1 files changed, 1 insertions, 1 deletions

diff --git a/arabluatex.lua b/arabluatex.lua
index 84562be..4ff7538 100644
--- a/arabluatex.lua
+++ b/arabluatex.lua
@@ -204,7 +204,7 @@ local function processarbnull(str, scheme)
    else
       str = string.gsub(str, "(\\arbnull.?)(%b{})", function(tag, body)
                            body = string.sub(body, 2, -2)
-                           return string.format("o%so", body)
+                           return string.format("O%sO", body)
       end)
    end
    return str