diff -ru a/lib/redmine/export/pdf.rb b/lib/redmine/export/pdf.rb
--- a/lib/redmine/export/pdf.rb	2011-04-02 12:06:35.000000000 +0900
+++ b/lib/redmine/export/pdf.rb	2011-04-02 12:06:46.000000000 +0900
@@ -179,8 +179,7 @@
 
       # Returns a PDF string of a list of issues
       def issues_to_pdf(issues, project, query)
-        if Redmine::Platform.mswin? ||
-           ( current_language.to_s.downcase == 'ko'    ||
+        if ( current_language.to_s.downcase == 'ko'    ||
              current_language.to_s.downcase == 'ja'    ||
              current_language.to_s.downcase == 'zh'    ||
              current_language.to_s.downcase == 'zh-tw' ||
@@ -259,8 +258,7 @@
 
       # Returns a PDF string of a single issue
       def issue_to_pdf(issue)
-        if Redmine::Platform.mswin? ||
-           ( current_language.to_s.downcase == 'ko'    ||
+        if ( current_language.to_s.downcase == 'ko'    ||
              current_language.to_s.downcase == 'ja'    ||
              current_language.to_s.downcase == 'zh'    ||
              current_language.to_s.downcase == 'zh-tw' ||
diff -ru a/lib/redmine/helpers/gantt.rb b/lib/redmine/helpers/gantt.rb
--- a/lib/redmine/helpers/gantt.rb	2011-04-02 12:06:29.000000000 +0900
+++ b/lib/redmine/helpers/gantt.rb	2011-04-02 12:06:43.000000000 +0900
@@ -507,8 +507,7 @@
       end if Object.const_defined?(:Magick)
 
       def to_pdf
-        if Redmine::Platform.mswin? ||
-           ( current_language.to_s.downcase == 'ko'    ||
+        if ( current_language.to_s.downcase == 'ko'    ||
              current_language.to_s.downcase == 'ja'    ||
              current_language.to_s.downcase == 'zh'    ||
              current_language.to_s.downcase == 'zh-tw' ||
diff -ru a/vendor/plugins/rfpdf/lib/tcpdf.rb b/vendor/plugins/rfpdf/lib/tcpdf.rb
--- a/vendor/plugins/rfpdf/lib/tcpdf.rb	2011-04-02 12:06:24.000000000 +0900
+++ b/vendor/plugins/rfpdf/lib/tcpdf.rb	2011-04-02 12:06:39.000000000 +0900
@@ -3063,7 +3063,7 @@
 			out('/Filter /FlateDecode');
 		end
 		out('>>');
-    open(ctgfile) do |f|
+    open(ctgfile, "rb") do |f|
       putstream(f.read())
     end
 		out('endobj');