diff --git a/Rakefile b/Rakefile
index 57f33b7..5ee89c8 100644
--- a/Rakefile
+++ b/Rakefile
@@ -38,8 +38,8 @@ end
 
 task :update_docs do
   ruby_path = File.join(
-    Config::CONFIG["bindir"],
-    Config::CONFIG["RUBY_INSTALL_NAME"])
+    RbConfig::CONFIG["bindir"],
+    RbConfig::CONFIG["RUBY_INSTALL_NAME"])
 
   help = "--help"
   command = "ruby #{File.basename(INSTALLER)} #{help}"
diff --git a/install.rb b/install.rb
index 18c80c8..bb917d6 100644
--- a/install.rb
+++ b/install.rb
@@ -12,7 +12,7 @@
 class Installer
   include FileUtils
 
-  CONFIG = Config::CONFIG
+  CONFIG = RbConfig::CONFIG
   BIT64 = (1.size == 8)
 
   RB_BASENAME = Pathname.new "P4.rb"
@@ -29,12 +29,17 @@ class Installer
   ]
 
   SERVER = "ftp.perforce.com"
-  SERVER_TOP_DIR = Pathname.new "perforce"
+  SERVER_TOP_DIR = Pathname.new "pub/perforce"
 
   # Mysterious "ghost" releases which lack files
-  HOSED_VERSIONS = %w[09.3 11.1]
+  HOSED_VERSIONS = %w[09.3 11.1 12.2]
+
+  if RUBY_PLATFORM == 'i386-mingw32'
+    P4API_REMOTE_BASENAME = Pathname.new "p4api.zip"
+  else
+    P4API_REMOTE_BASENAME = Pathname.new "p4api.tgz"
+  end
 
-  P4API_REMOTE_BASENAME = Pathname.new "p4api.tgz"
   P4RUBY_REMOTE_BASENAME = Pathname.new "p4ruby.tgz"
 
   WORK_DIR = Pathname.new "work"
@@ -199,6 +204,8 @@ def guess_platform(opts = {})
 
     if config_os =~ %r!cygwin!i
       "cygwin" + windows_cpu
+    elsif (config_os =~ %r!mingw!i) && (CONFIG["MAJOR"].to_i == 1) && (CONFIG["MINOR"].to_i == 9)
+      "mingw" + windows_cpu
     elsif config_os =~ %r!(mswin|mingw)!i
       "nt" + windows_cpu
     elsif @s.local
@@ -253,7 +260,11 @@ def sys(*args)
   end
 
   def unpack(distfile, target_dir)
-    sys("tar", "zxvf", distfile.to_s, "-C", target_dir.to_s)
+    if File.extname(distfile.to_s).downcase == '.zip'
+      sys('unzip', distfile.to_s, '-d', target_dir.to_s)
+    else
+      sys("tar", "zxvf", distfile.to_s, "-C", target_dir.to_s)
+    end
   end
 
   def fetch_spec(spec)