diff --git a/lib/MooseX/Types.pm b/lib/MooseX/Types.pm
index aa8d3af..200010e 100644
--- a/lib/MooseX/Types.pm
+++ b/lib/MooseX/Types.pm
@@ -486,8 +486,8 @@ This generates a coercion handler function, e.g. C<to_Int($value)>.
 =cut
 
 sub coercion_export_generator {
-    my ($class, $type, $full, $undef_msg) = @_;
-    return defer_sub undef, sub {
+    my ($class, $sub_name, $type, $full, $undef_msg) = @_;
+    return defer_sub $sub_name, sub {
         my ($value) = @_;
 
         # we need a type object
@@ -511,9 +511,9 @@ Generates a constraint check closure, e.g. C<is_Int($value)>.
 =cut
 
 sub check_export_generator {
-    my ($class, $type, $full, $undef_msg) = @_;
+    my ($class, $sub_name, $type, $full, $undef_msg) = @_;
 
-    return defer_sub undef, sub {
+    return defer_sub $sub_name, sub {
         my ($value) = @_;
 
         # we need a type object
diff --git a/lib/MooseX/Types/Base.pm b/lib/MooseX/Types/Base.pm
index 92a2c06..780d231 100644
--- a/lib/MooseX/Types/Base.pm
+++ b/lib/MooseX/Types/Base.pm
@@ -53,8 +53,18 @@ sub import {
     # determine the wrapper, -into is supported for compatibility reasons
     my $wrapper = $options->{ -wrapper } || 'MooseX::Types';
 
-    $args[0]->{into} = $options->{ -into }
-        if exists $options->{ -into };
+    # It's a little gross to calculate the calling package here when
+    # Sub::Exporter is going to do it again, but we need to give Sub::Defer a
+    # fully qualified name if we give it a name at all, and we want to give it
+    # a name. Otherwise it guesses at the name and will use its caller, which
+    # in this case ends up being MooseX::Types, which is wrong.
+    my $into;
+    if (exists $options->{ -into }) {
+        $into = $args[0]->{into} = $options->{ -into }
+    }
+    else {
+        $into = caller(($options->{into_level} || 0) + 1)
+    }
 
     my %ex_util;
 
@@ -79,7 +89,7 @@ sub import {
         my $check_name = "is_${type_short}";
         push @{ $ex_spec{exports} },
             $check_name,
-            sub { $wrapper->check_export_generator($type_short, $type_full, $undef_msg) };
+            sub { $wrapper->check_export_generator("${into}::$check_name", $type_short, $type_full, $undef_msg) };
 
         # only export coercion helper if full (for libraries) or coercion is defined
         next TYPE
@@ -89,7 +99,7 @@ sub import {
         my $coercion_name = "to_${type_short}";
         push @{ $ex_spec{exports} },
             $coercion_name,
-            sub { $wrapper->coercion_export_generator($type_short, $type_full, $undef_msg) };
+            sub { $wrapper->coercion_export_generator("${into}::$coercion_name", $type_short, $type_full, $undef_msg) };
         $ex_util{ $type_short }{to}++;  # shortcut to remember this exists
     }
 
diff --git a/t/27-sub-defer.t b/t/27-sub-defer.t
new file mode 100644
index 0000000..a73eef9
--- /dev/null
+++ b/t/27-sub-defer.t
@@ -0,0 +1,28 @@
+use strict;
+use warnings;
+
+use Test::More 0.88;
+use if $ENV{AUTHOR_TESTING}, 'Test::Warnings';
+
+use Test::Fatal;
+use B::Deparse;
+use MooseX::Types::Moose qw( Int );
+use Sub::Defer qw( undefer_all );
+
+like(
+    B::Deparse->new->coderef2text( \&is_Int ),
+    qr/package Sub::Defer/,
+    'is_Int sub has not yet been undeferred'
+);
+is(
+    exception { undefer_all() },
+    undef,
+    'Sub::Defer::undefer_all works with subs exported by MooseX::Types'
+);
+unlike(
+    B::Deparse->new->coderef2text( \&is_Int ),
+    qr/package Sub::Defer/,
+    'is_Int sub is now undeferred'
+);
+
+done_testing();