diff --git a/R/S3.R b/R/S3.R
index 7e1e162..8ce4eab 100644
--- a/R/S3.R
+++ b/R/S3.R
@@ -29,7 +29,7 @@ register_s3_method <- function(x, env){
 
   parts <- unlist(strsplit(x, split=".", fixed=TRUE))
   generic <- parts[1]
-  class <- paste(parts[-1], sep=".")
+  class <- paste0(parts[-1], collapse=".")
 
   registerS3method(generic, class, method, env)
 
diff --git a/tests/test_import/module_S3.R b/tests/test_import/module_S3.R
index 3258003..0d55b44 100644
--- a/tests/test_import/module_S3.R
+++ b/tests/test_import/module_S3.R
@@ -16,3 +16,8 @@ test_fun.numeric <- function(x){
 print.test_class <- function(x){
   print(as.character(x))
 }
+
+# a method for class with dot in name
+test_fun.data.frame = function(x){
+    structure("data.frame", class = "test_class")
+    }
diff --git a/tests/test_import/test_S3.R b/tests/test_import/test_S3.R
index 7e4c5f1..10da865 100644
--- a/tests/test_import/test_S3.R
+++ b/tests/test_import/test_S3.R
@@ -29,6 +29,7 @@ test_that("S3 methods are registered", {
   expect_silent( import::from("module_S3.R", "test_fun", .S3=TRUE) )
   expect_identical( test_fun(1), structure("numeric", class="test_class") )
   expect_identical( test_fun("1"), structure("character", class="test_class") )
+  expect_identical( test_fun(data.frame()), structure("data.frame", class="test_class"))
   expect_output( print(test_fun(1)), "numeric" )
   expect_output( print(test_fun("OK")), "character" )
   cleanup_environment()