diff --git a/lib/mechanize.rb b/lib/mechanize.rb
index 17765051..4e8d0341 100644
--- a/lib/mechanize.rb
+++ b/lib/mechanize.rb
@@ -717,10 +717,10 @@ class << self
   # authentication.
 
   def auth user, password, domain = nil
-    caller.first =~ /(.*?):(\d+).*?$/
+    c = caller_locations(1,1).first
 
     warn <<-WARNING
-At #{$1} line #{$2}
+At #{c.absolute_path} line #{c.lineno}
 
 Use of #auth and #basic_auth are deprecated due to a security vulnerability.
 
diff --git a/lib/mechanize/cookie.rb b/lib/mechanize/cookie.rb
index 2d001e80..fe7eb366 100644
--- a/lib/mechanize/cookie.rb
+++ b/lib/mechanize/cookie.rb
@@ -7,7 +7,7 @@ class Mechanize
   module CookieDeprecated
     def __deprecated__(to = nil)
       $VERBOSE or return
-      method = caller[0][/([^`]+)(?='$)/]
+      method = caller_locations(1,1).first.base_label
       to ||= method
       case self
       when Class
@@ -21,7 +21,7 @@ def __deprecated__(to = nil)
         this = '%s#%s' % [klass, method]
         that = 'HTTP::%s#%s' % [lname, to]
       end
-      warn '%s: The call of %s needs to be fixed to follow the new API (%s).' % [caller[1], this, that]
+      warn '%s: The call of %s needs to be fixed to follow the new API (%s).' % [caller_locations(2,1).first, this, that]
     end
     private :__deprecated__
   end
diff --git a/test/test_mechanize_http_agent.rb b/test/test_mechanize_http_agent.rb
index f2fea1e7..0c327868 100644
--- a/test/test_mechanize_http_agent.rb
+++ b/test/test_mechanize_http_agent.rb
@@ -29,7 +29,7 @@ def auth_realm uri, scheme, type
 
   def skip_if_jruby_zlib
     if RUBY_ENGINE == 'jruby'
-      meth = caller[0][/`(\w+)/, 1]
+      meth = caller_locations(1,1).first.base_label
       skip "#{meth}: skipped because how Zlib handles error is different in JRuby"
     end
   end
diff --git a/test/test_mechanize_page_link.rb b/test/test_mechanize_page_link.rb
index 520a13c1..1be78fcf 100644
--- a/test/test_mechanize_page_link.rb
+++ b/test/test_mechanize_page_link.rb
@@ -55,7 +55,7 @@ def util_page body = @body, res = @res
 
   def skip_if_nkf_dependency
     if RUBY_ENGINE == 'jruby'
-      meth = caller[0][/`(\w+)/, 1]
+      meth = caller_locations(1,1).first.base_label
       skip "#{meth}: skipped because this feature currently depends on NKF"
     end
   end